[2021] Crash when modifying colony

By "modifying colonies" do you mean editing your save game files? Or using the command console?  

I see. Can you test if that also happens for you, in a campaign that's never had any mods used in it?  

Disabling mods does not remove effects they've already had on the save game file.

If you get this in a campaign that's never had any mods used in it please let us know!