cross context join asp.net core

Question

I am doing project in ASP.NET Core MVC with Entity Framework Core.

I have two databases as contexts and I need to push to index this SQL:

SELECT 
    * 
FROM 
    db1.table1 AS tpt
JOIN 
    db2.table1 AS ta ON tpt.cIBAN = ta.cIBAN
JOIN
    db2.table2 AS tpa ON ta.nAccountID = tpa.nAccountID 
JOIN
    db2.table3 AS tc ON tc.nClientID = ta.nAccountID
WHERE
    ta.lActive = 1;

What I made so far is this

var query = await (from tpt in context1.table1
                   join ta in context2.table1 on tpt.CIban equals ta.CIban
                   join tpa in context2.table2 on ta.NAccountId equals tpa.NAccountId
                   join tc in context2.table3 on ta.NAccountId equals tc.NClientId
                   where ta.LActive == true
                   select new
                        {
                            tpt.DRegister,
                            tc.CNameOnPaymentCard,
                            tc.NClientId,
                            tpt.CIban,
                            tpt.CCurrency,
                            ta.NCurrency,
                            tpt.DValidityFrom,
                            tpt.DValidityTo,
                            tpt.CNote
                        }).ToListAsync();

However this will not work as I can not use query on two contexts at the same time.

Would really appreciate any help. Thanks, it bothers me for some time now....

EDIT:

I fixed the problem by splitting query into two LINQ statements returning lists and then concatenating two lists into one list of class. Not best solution, its hideous and slow. However, its working.

Solution:

var x = context1.table1.ToList();
var y = (from ta in context2.table1
                           join tc in context.table2 on ta.NAccountId 
                           equals tc.NClientId
                           where ta.LActive == true
                           select new {
                                thingsI_NeededToList
                                ...
                           }).ToList();

var xy = from table1 in y
         join table2 in x on table1.CIban equals table2.CIban
         select new ClassINeededToPass
         {
         ClassParameter = table1.parameter
         ...
         };