I use text replacement on my iPhone, and these are syncing to my Mac via iCloud. But I don't want to use them on my Mac, because I use TextExpander. How can I prevent the text replacement on my Mac, but keep the text replacement on my iPhone?
Text replacement can be accessed via System Preferences → Keyboard → Text.
Below is a screenshot of the text replacement list in System Preferences.
To disable this globally on your Mac, you'll use need to use the defaults command (see here for more info). This command only applies to your macOS instance. Open the terminal (see here if you don't know how to open the terminal) and type:
defaults write -g WebAutomaticTextReplacementEnabled -bool false
And to enable it again; you can just switch the last word to true and type the whole thing in the terminal again:
defaults write -g WebAutomaticTextReplacementEnabled -bool true
You can also disable text replacement on an application-by-application basis by having the application open (let's say Safari), and then up in the menu, clicking the Edit → Substitutions then unchecking Text Replacement.
More information is found in this article.
