Universal Solution & Meta-Analysis of All Solutions
TLDR:
For the solution, skip to the section The Solutions
 
For the meta-analysis, skip to the section Testing and comparison of solutions
 
Background
In the last few months, @Cristian Buse (GitHub) and I performed extensive research and work on the problem in question, which led to the discovery of a large number of cases no previously available solution could solve. Because of this, we started refining our own solutions.
Unfortunately, throughout development, our solutions grew very complex. Describing how exactly they work would go far beyond the scope of a single StackOverflow answer.
For those who are interested in these technicalities, here are links to the threads we used to discuss our progress: Thread 1, Thread 2. The total volume of these threads is approximately 40,000 words or 150 pages. Luckily, it is not necessary to understand any of that to harvest the fruits of our efforts.
In the end, both of us created independent solutions:
@Cristian Buse developed his solution as part of one of his excellent VBA Libraries, to be specific, the Library VBA-FileTools. It is implemented elegantly and stepping through his code is the best way of comprehending how the solution works in detail. Furthermore, his library provides a bunch of other very useful functionalities.
 
My own solution comes in the form of a standalone function without any dependencies. This is useful if this problem occurs in a small project where no additional functionality is required. Because implementing the desired universal functionality is complex, it is very long and convoluted for a single procedure. I do not recommend trying to comprehend the solution by reading the code of this function.
 
Since the creation of our solutions, we continued to work on them improving the functionality and fixing various bugs.
The Solutions
NOTE: Should you encounter any bugs with our solutions, please report them here or on GitHub! In that case, I recommend you use this solution in the meantime, as it is the next most accurate solution available.
Solution 1 - Library
Import this library: VBA-FileTools
 from GitHub into your project. Getting the local name of your workbook is then as easy as:
GetLocalPath(ThisWorkbook.FullName)
Note: Full Mac support was added to this solution on Apr 5, 2023.
Solution 2 - Standalone Function
Copy this function, either from GitHub Gist or from this answer directly, into any standard code module. The version on GitHub Gist includes more information and some comments in and on the code.
Getting the local name of your workbook now works in the same way as with Solution 1:
GetLocalPath(ThisWorkbook.FullName)
Note that this function also offers some optional parameters, but they should almost never be needed. (See Gist for more information)
Note: Partial Mac support was added to this solution on Dec 20, 2022, and full support on Mar 20, 2023.
Important: Currently, only the Gist version contains the full Mac support implementation because it doesn't fit into this StackOverflow answer!
Here is the code of the function:
'This Function will convert a OneDrive/SharePoint Url path, e.g. Url containing
'https://d.docs.live.net/; .sharepoint.com/sites; my.sharepoint.com/personal/...
'to the locally synchronized path on your current pc or mac, e.g. a path like
'C:\users\username\OneDrive\ on Windows; or /Users/username/OneDrive/ on MacOS,
'if you have the remote directory locally synchronized with the OneDrive app.
'If no local path can be found, the input value will be returned unmodified.
'Author: Guido Witt-Dörring
'Source: https://gist.github.com/guwidoe/038398b6be1b16c458365716a921814d
Public Function GetLocalPath(ByVal path As String, _
                    Optional ByVal rebuildCache As Boolean = False, _
                    Optional ByVal returnAll As Boolean = False, _
                    Optional ByVal preferredMountPointOwner As String = "") _
                             As String
    #If Mac Then
        Const vbErrPermissionDenied As Long = 70
        Const vbErrInvalidFormatInResourceFile As Long = 325
        Const ps As String = "/"
    #Else
        Const ps As String = "\"
    #End If
    Const vbErrFileNotFound As Long = 53
    Const vbErrOutOfMemory As Long = 7
    Const vbErrKeyAlreadyExists As Long = 457
    Const chunkOverlap As Long = 1000
    Static locToWebColl As Collection, lastTimeNotFound As Collection
    Static lastCacheUpdate As Date
    Dim resColl As Object, webRoot As String, locRoot As String
    Dim vItem As Variant, s As String, keyExists As Boolean
    Dim pmpo As String: pmpo = LCase(preferredMountPointOwner)
    If Not locToWebColl Is Nothing And Not rebuildCache Then
        Set resColl = New Collection: GetLocalPath = ""
        For Each vItem In locToWebColl
            locRoot = vItem(0): webRoot = vItem(1)
            If InStr(1, path, webRoot, vbTextCompare) = 1 Then _
                resColl.Add Key:=vItem(2), _
                   Item:=Replace(Replace(path, webRoot, locRoot, , 1), "/", ps)
        Next vItem
        If resColl.Count > 0 Then
            If returnAll Then
                For Each vItem In resColl: s = s & "//" & vItem: Next vItem
                GetLocalPath = Mid(s, 3): Exit Function
            End If
            On Error Resume Next: GetLocalPath = resColl(pmpo): On Error GoTo 0
            If GetLocalPath <> "" Then Exit Function
            GetLocalPath = resColl(1): Exit Function
        End If
        If Not lastTimeNotFound Is Nothing Then
            On Error Resume Next: lastTimeNotFound path
            keyExists = (Err.Number = 0): On Error GoTo 0
            If keyExists Then
                If DateAdd("s", 1, lastTimeNotFound(path)) > Now() Then _
                    GetLocalPath = path: Exit Function
            End If
        End If
        GetLocalPath = path
    End If
    Dim cid As String, fileNum As Long, line As Variant, parts() As String
    Dim tag As String, mainMount As String, relPath As String, email As String
    Dim b() As Byte, n As Long, i As Long, size As Long, libNr As String
    Dim parentID As String, folderID As String, folderName As String
    Dim folderIdPattern As String, fileName As String, folderType As String
    Dim siteID As String, libID As String, webID As String, lnkID As String
    Dim odFolders As Object, cliPolColl As Object, libNrToWebColl As Object
    Dim sig1 As String: sig1 = StrConv(Chr$(&H2), vbFromUnicode)
    Dim sig2 As String: sig2 = ChrW$(&H1) & String(3, vbNullChar)
    Dim vbNullByte As String: vbNullByte = MidB$(vbNullChar, 1, 1)
    Dim buffSize As Long, lastChunkEndPos As Long, lenDatFile As Long
    Dim lastFileUpdate As Date
    #If Mac Then
        Dim utf16() As Byte, utf32() As Byte, j As Long, k As Long, m As Long
        Dim charCode As Long, lowSurrogate As Long, highSurrogate As Long
        ReDim b(0 To 3): b(0) = &HAB&: b(1) = &HAB&: b(2) = &HAB&: b(3) = &HAB&
        Dim sig3 As String: sig3 = b: sig3 = vbNullChar & vbNullChar & sig3
    #Else
        ReDim b(0 To 1): b(0) = &HAB&: b(1) = &HAB&
        Dim sig3 As String: sig3 = b: sig3 = vbNullChar & sig3
    #End If
    Dim settPath As String, wDir As String, clpPath As String
    #If Mac Then
        s = Environ("HOME")
        settPath = Left(s, InStrRev(s, "/Library/Containers/")) & _
                   "Library/Containers/com.microsoft.OneDrive-mac/Data/" & _
                   "Library/Application Support/OneDrive/settings/"
        clpPath = s & "/Library/Application Support/Microsoft/Office/CLP/"
    #Else
        settPath = Environ("LOCALAPPDATA") & "\Microsoft\OneDrive\settings\"
        clpPath = Environ("LOCALAPPDATA") & "\Microsoft\Office\CLP\"
    #End If
    #If Mac Then
        Dim possibleDirs(0 To 11) As String: possibleDirs(0) = settPath
        For i = 1 To 9: possibleDirs(i) = settPath & "Business" & i & ps: Next i
       possibleDirs(10) = settPath & "Personal" & ps: possibleDirs(11) = clpPath
        If Not GrantAccessToMultipleFiles(possibleDirs) Then _
            Err.Raise vbErrPermissionDenied
    #End If
    Dim oneDriveSettDirs As Collection: Set oneDriveSettDirs = New Collection
    Dim dirName As Variant: dirName = Dir(settPath, vbDirectory)
    Do Until dirName = ""
        If dirName = "Personal" Or dirName Like "Business#" Then _
            oneDriveSettDirs.Add dirName
        dirName = Dir(, vbDirectory)
    Loop
    #If Mac Then
        s = ""
        For Each dirName In oneDriveSettDirs
            wDir = settPath & dirName & ps
            cid = IIf(dirName = "Personal", "????????????????", _
                      "????????-????-????-????-????????????")
           If dirName = "Personal" Then s = s & "//" & wDir & "GroupFolders.ini"
            s = s & "//" & wDir & "global.ini"
            fileName = Dir(wDir, vbNormal)
            Do Until fileName = ""
                If fileName Like cid & ".ini" Or _
                   fileName Like cid & ".dat" Or _
                   fileName Like "ClientPolicy*.ini" Then _
                    s = s & "//" & wDir & fileName
                fileName = Dir
            Loop
        Next dirName
        If Not GrantAccessToMultipleFiles(Split(Mid(s, 3), "//")) Then _
            Err.Raise vbErrPermissionDenied
    #End If
    If Not locToWebColl Is Nothing And Not rebuildCache Then
        s = ""
        For Each dirName In oneDriveSettDirs
            wDir = settPath & dirName & ps
            cid = IIf(dirName = "Personal", "????????????????", _
                      "????????-????-????-????-????????????")
            If Dir(wDir & "global.ini") <> "" Then _
                s = s & "//" & wDir & "global.ini"
            fileName = Dir(wDir, vbNormal)
            Do Until fileName = ""
                If fileName Like cid & ".ini" Then s = s & "//" & _
                                                       wDir & fileName
                fileName = Dir
            Loop
        Next dirName
        For Each vItem In Split(Mid(s, 3), "//")
            If FileDateTime(vItem) > lastCacheUpdate Then _
                rebuildCache = True: Exit For
        Next vItem
        If Not rebuildCache Then
            If lastTimeNotFound Is Nothing Then _
                Set lastTimeNotFound = New Collection
            On Error Resume Next: lastTimeNotFound.Remove path: On Error GoTo 0
            lastTimeNotFound.Add Item:=Now(), Key:=path
            Exit Function
        End If
    End If
    lastCacheUpdate = Now()
    Set lastTimeNotFound = Nothing
    Set locToWebColl = New Collection
    For Each dirName In oneDriveSettDirs
        wDir = settPath & dirName & ps
        If Dir(wDir & "global.ini", vbNormal) = "" Then GoTo NextFolder
        fileNum = FreeFile()
        Open wDir & "global.ini" For Binary Access Read As #fileNum
            ReDim b(0 To LOF(fileNum)): Get fileNum, , b
        Close #fileNum: fileNum = 0
        #If Mac Then
            b = StrConv(b, vbUnicode)
        #End If
        For Each line In Split(b, vbNewLine)
            If line Like "cid = *" Then cid = Mid(line, 7): Exit For
        Next line
        If cid = "" Then GoTo NextFolder
        If (Dir(wDir & cid & ".ini") = "" Or _
            Dir(wDir & cid & ".dat") = "") Then GoTo NextFolder
        If dirName Like "Business#" Then
            folderIdPattern = Replace(Space(32), " ", "[a-f0-9]")
        ElseIf dirName = "Personal" Then
            folderIdPattern = Replace(Space(16), " ", "[A-F0-9]") & "!###*"
        End If
        fileName = Dir(clpPath, vbNormal)
        Do Until fileName = ""
            i = InStrRev(fileName, cid, , vbTextCompare)
            If i > 1 And cid <> "" Then _
                email = LCase(Left(fileName, i - 2)): Exit Do
            fileName = Dir
        Loop
        Set cliPolColl = New Collection
        fileName = Dir(wDir, vbNormal)
        Do Until fileName = ""
            If fileName Like "ClientPolicy*.ini" Then
                fileNum = FreeFile()
                Open wDir & fileName For Binary Access Read As #fileNum
                    ReDim b(0 To LOF(fileNum)): Get fileNum, , b
                Close #fileNum: fileNum = 0
                #If Mac Then
                    b = StrConv(b, vbUnicode)
                #End If
                cliPolColl.Add Key:=fileName, Item:=New Collection
                For Each line In Split(b, vbNewLine)
                    If InStr(1, line, " = ", vbBinaryCompare) Then
                        tag = Left(line, InStr(line, " = ") - 1)
                        s = Mid(line, InStr(line, " = ") + 3)
                        Select Case tag
                        Case "DavUrlNamespace"
                            cliPolColl(fileName).Add Key:=tag, Item:=s
                        Case "SiteID", "IrmLibraryId", "WebID"
                            s = Replace(LCase(s), "-", "")
                            If Len(s) > 3 Then s = Mid(s, 2, Len(s) - 2)
                            cliPolColl(fileName).Add Key:=tag, Item:=s
                        End Select
                    End If
                Next line
            End If
            fileName = Dir
        Loop
        buffSize = -1
Try:    On Error GoTo Catch
        Set odFolders = New Collection
        lastChunkEndPos = 1: i = 0
        lastFileUpdate = FileDateTime(wDir & cid & ".dat")
        Do
            If FileDateTime(wDir & cid & ".dat") > lastFileUpdate Then GoTo Try
            fileNum = FreeFile
            Open wDir & cid & ".dat" For Binary Access Read As #fileNum
                lenDatFile = LOF(fileNum)
                If buffSize = -1 Then buffSize = lenDatFile
                ReDim b(0 To buffSize + chunkOverlap)
                Get fileNum, lastChunkEndPos, b: s = b: size = LenB(s)
            Close #fileNum: fileNum = 0
            lastChunkEndPos = lastChunkEndPos + buffSize
            For vItem = 16 To 8 Step -8
                i = InStrB(vItem + 1, s, sig2)
                Do While i > vItem And i < size - 168
                    If MidB$(s, i - vItem, 1) = sig1 Then
                        i = i + 8: n = InStrB(i, s, vbNullByte) - i
                        If n < 0 Then n = 0
                        If n > 39 Then n = 39
                        folderID = StrConv(MidB$(s, i, n), vbUnicode)
                        i = i + 39: n = InStrB(i, s, vbNullByte) - i
                        If n < 0 Then n = 0
                        If n > 39 Then n = 39
                        parentID = StrConv(MidB$(s, i, n), vbUnicode)
                        i = i + 121: n = -Int(-(InStrB(i, s, sig3) - i) / 2) * 2
                        If n < 0 Then n = 0
                        #If Mac Then
                            utf32 = MidB$(s, i, n)
                            ReDim utf16(LBound(utf32) To UBound(utf32))
                            j = LBound(utf32): k = LBound(utf32)
                            Do While j < UBound(utf32)
                                If utf32(j + 2) = 0 And utf32(j + 3) = 0 Then
                                    utf16(k) = utf32(j)
                                    utf16(k + 1) = utf32(j + 1)
                                    k = k + 2
                                Else
                                    If utf32(j + 3) <> 0 Then Err.Raise _
                                        vbErrInvalidFormatInResourceFile
                                    charCode = utf32(j + 2) * &H10000 + _
                                               utf32(j + 1) * &H100& + utf32(j)
                                    m = charCode - &H10000
                                    highSurrogate = &HD800& + (m \ &H400&)
                                    lowSurrogate = &HDC00& + (m And &H3FF)
                                    utf16(k) = CByte(highSurrogate And &HFF&)
                                    utf16(k + 1) = CByte(highSurrogate \ &H100&)
                                    utf16(k + 2) = CByte(lowSurrogate And &HFF&)
                                    utf16(k + 3) = CByte(lowSurrogate \ &H100&)
                                    k = k + 4
                                End If
                                j = j + 4
                            Loop
                            ReDim Preserve utf16(LBound(utf16) To k - 1)
                            folderName = utf16
                        #Else
                            folderName = MidB$(s, i, n)
                        #End If
                        If folderID Like folderIdPattern Then
                            odFolders.Add VBA.Array(parentID, folderName), _
                                          folderID
                        End If
                    End If
                    i = InStrB(i + 1, s, sig2)
                Loop
                If odFolders.Count > 0 Then Exit For
            Next vItem
        Loop Until lastChunkEndPos >= lenDatFile _
                Or buffSize >= lenDatFile
        GoTo Continue
Catch:
        If Err.Number = vbErrKeyAlreadyExists Then
            odFolders.Remove folderID
            Resume
        End If
        If Err.Number <> vbErrOutOfMemory Then Err.Raise Err
        If buffSize > &HFFFFF Then buffSize = buffSize / 2: Resume Try
        Err.Raise Err
Continue: On Error GoTo 0
        fileNum = FreeFile()
        Open wDir & cid & ".ini" For Binary Access Read As #fileNum
            ReDim b(0 To LOF(fileNum)): Get fileNum, , b
        Close #fileNum: fileNum = 0
        #If Mac Then
            b = StrConv(b, vbUnicode)
        #End If
        Select Case True
        Case dirName Like "Business#"
            mainMount = "": Set libNrToWebColl = New Collection
            For Each line In Split(b, vbNewLine)
                webRoot = "": locRoot = ""
                Select Case Left$(line, InStr(line, " = ") - 1)
                Case "libraryScope"
                    parts = Split(line, """"): locRoot = parts(9)
                    If locRoot = "" Then libNr = Split(line, " ")(2)
                    folderType = parts(3): parts = Split(parts(8), " ")
                    siteID = parts(1): webID = parts(2): libID = parts(3)
                    If mainMount = "" And folderType = "ODB" Then
                        mainMount = locRoot: fileName = "ClientPolicy.ini"
                    Else: fileName = "ClientPolicy_" & libID & siteID & ".ini"
                    End If
                    On Error Resume Next
                    webRoot = cliPolColl(fileName)("DavUrlNamespace")
                    On Error GoTo 0
                    If webRoot = "" Then
                        For Each vItem In cliPolColl
                            If vItem("SiteID") = siteID _
                            And vItem("WebID") = webID _
                            And vItem("IrmLibraryId") = libID Then
                                webRoot = vItem("DavUrlNamespace"): Exit For
                            End If
                        Next vItem
                    End If
                    If webRoot = "" Then Err.Raise vbErrFileNotFound
                    If locRoot = "" Then
                        libNrToWebColl.Add VBA.Array(libNr, webRoot), libNr
                    Else: locToWebColl.Add VBA.Array(locRoot, webRoot, email) _
                                           , locRoot
                    End If
                Case "libraryFolder"
                    locRoot = Split(line, """")(1): libNr = Split(line, " ")(3)
                    For Each vItem In libNrToWebColl
                        If vItem(0) = libNr Then
                            s = "": parentID = Left(Split(line, " ")(4), 32)
                            Do
                                On Error Resume Next: odFolders parentID
                                keyExists = (Err.Number = 0): On Error GoTo 0
                                If Not keyExists Then Exit Do
                                s = odFolders(parentID)(1) & "/" & s
                                parentID = odFolders(parentID)(0)
                            Loop
                            webRoot = vItem(1) & s: Exit For
                        End If
                    Next vItem
                    locToWebColl.Add VBA.Array(locRoot, webRoot, email), locRoot
                Case "AddedScope"
                    parts = Split(line, """")
                    relPath = parts(5): If relPath = " " Then relPath = ""
                    parts = Split(parts(4), " "): siteID = parts(1)
                    webID = parts(2): libID = parts(3): lnkID = parts(4)
                    fileName = "ClientPolicy_" & libID & siteID & lnkID & ".ini"
                    On Error Resume Next
                    webRoot = cliPolColl(fileName)("DavUrlNamespace") & relPath
                    On Error GoTo 0
                    If webRoot = "" Then
                        For Each vItem In cliPolColl
                            If vItem("SiteID") = siteID _
                            And vItem("WebID") = webID _
                            And vItem("IrmLibraryId") = libID Then
                                webRoot = vItem("DavUrlNamespace") & relPath
                                Exit For
                            End If
                        Next vItem
                    End If
                    If webRoot = "" Then Err.Raise vbErrFileNotFound
                    s = "": parentID = Left(Split(line, " ")(3), 32)
                    Do
                        On Error Resume Next: odFolders parentID
                        keyExists = (Err.Number = 0): On Error GoTo 0
                        If Not keyExists Then Exit Do
                        s = odFolders(parentID)(1) & ps & s
                        parentID = odFolders(parentID)(0)
                    Loop
                    locRoot = mainMount & ps & s
                    locToWebColl.Add VBA.Array(locRoot, webRoot, email), locRoot
                Case Else
                    Exit For
                End Select
            Next line
        Case dirName = "Personal"
            For Each line In Split(b, vbNewLine)
                If line Like "library = *" Then _
                    locRoot = Split(line, """")(3): Exit For
            Next line
            On Error Resume Next
            webRoot = cliPolColl("ClientPolicy.ini")("DavUrlNamespace")
            On Error GoTo 0
            If locRoot = "" Or webRoot = "" Or cid = "" Then GoTo NextFolder
            locToWebColl.Add VBA.Array(locRoot, webRoot & "/" & cid, email), _
                             locRoot
            If Dir(wDir & "GroupFolders.ini") = "" Then GoTo NextFolder
            cid = "": fileNum = FreeFile()
            Open wDir & "GroupFolders.ini" For Binary Access Read As #fileNum
                ReDim b(0 To LOF(fileNum)): Get fileNum, , b
            Close #fileNum: fileNum = 0
            #If Mac Then
                b = StrConv(b, vbUnicode)
            #End If
            For Each line In Split(b, vbNewLine)
                If InStr(line, "BaseUri = ") And cid = "" Then
                    cid = LCase(Mid(line, InStrRev(line, "/") + 1, 16))
                    folderID = Left(line, InStr(line, "_") - 1)
                ElseIf cid <> "" Then
                    locToWebColl.Add VBA.Array(locRoot & ps & odFolders( _
                                     folderID)(1), webRoot & "/" & cid & "/" & _
                                     Mid(line, Len(folderID) + 9), email), _
                                     locRoot & ps & odFolders(folderID)(1)
                    cid = "": folderID = ""
                End If
            Next line
        End Select
NextFolder:
        cid = "": s = "": email = "": Set odFolders = Nothing
    Next dirName
    Dim tmpColl As Collection: Set tmpColl = New Collection
    For Each vItem In locToWebColl
        locRoot = vItem(0): webRoot = vItem(1): email = vItem(2)
       If Right(webRoot, 1) = "/" Then webRoot = Left(webRoot, Len(webRoot) - 1)
        If Right(locRoot, 1) = ps Then locRoot = Left(locRoot, Len(locRoot) - 1)
        tmpColl.Add VBA.Array(locRoot, webRoot, email), locRoot
    Next vItem
    Set locToWebColl = tmpColl
    GetLocalPath = GetLocalPath(path, False, returnAll, pmpo): Exit Function
End Function
How Do the Solutions Work?
Both solutions get all of the required information for translating the UrlPath/WebPath to a LocalPath from the OneDrive settings files inside of the directory %localappdata%\Microsoft\OneDrive\settings\....
This means, contrary to most other solutions online, the registry is not used! The reasons for this are explained in the Gist repository of Solution 2.
The following files will be read:
(Wildcards: * - zero or more characters; ? - one character)
????????????????.dat
????????????????.ini
global.ini
GroupFolders.ini
????????-????-????-????-????????????.dat
????????-????-????-????-????????????.ini
ClientPolicy*.ini
All of the .ini files can be read easily as they use UTF-16 encoding.
The .dat files are much more difficult to decipher, because they use a proprietary binary format. Luckily, the information we need can be extracted by looking for certain byte-patterns inside these files and copying and converting the data at a certain offset from these "signature" bytes.
Data from all of these files is used, to create a "dictionary" of all the local mount points on your pc, and their corresponding WebPath. For example, for your personal OneDrive, such a local mount point could look like this:
C:\Users\Username\OneDrive, and the corresponding WebPath could look like this: https://d.docs.live.net/f9d8c1184686d493.
This "dictionary" can then be used to "translate" a given WebPath to a local path by replacing the part that is equal to one of the elements of the dictionary with the corresponding local mount point. For example, this WebPath: https://d.docs.live.net/f9d8c1184686d493/Folder/File.xlsm will be correctly "translated" to C:\Users\Username\OneDrive\Folder\File.xlsm
Because all possible WebPaths for the local machine can be translated by the same dictionary, it is implemented as Static in both solutions. This means it will only be written the first time the function is called, all subsequent function calls will find the "dictionary" already initialized leading to shorter run time.
Testing and Comparison of Solutions
I conducted extensive testing of all solutions I could find online. A selection of these tests will be presented here.
This is a list of some of the tested solutions:
Each line in the table in the below image represents one solution in the above table and they can be correlated using the solution number.
Likewise, each column represents a test case, they can be correlated to this test-table by using the test-number. Unfortunately Stack Overflow doesn't allow answers long enough to include the table of test cases directly in this post.

All of this testing was done on Windows. On macOS, every solution except for Nr 32 and Nr 33 would pass 0/46 tests. The solutions presented in this post (#32 and #33) also pass every test on macOS.
Most solutions pass very few tests. Many of these tests are relatively dificult to solve, some are absolute edge cases, such as tests Nr 41 to 46, that test how a solution deals with OneDrive folders that are synced to multiple different local paths, which can only happen if multiple Business OneDrive accounts are logged in on the same PC and even then needs some special setup. (More information on that can be found here in Thread 2)
Test Nr 22 contains various Unicode emoji characters in some folder names, this is why many solutions fail with error here.
Another reason why many solutions perform poorly is that the environment variables Environ("OneDrive"), Environ("OneDriveCommercial"),Environ("OneDriveConsumer"), which many solutions build on, are not reliable, especially when you have multiple business OneDrive accounts logged in at the same time, like I do. Note that even if they always returned their expected values, it would be way to little information to solve all cases.
If you have another different solution you would like me to test, let me know and I'll add it to this section.