[Suicide Junkie]

That's correct. All I had to do was start a game with random empires, then save all of them.

For my mod, everybody had to have the "normal" racial trait, so you have to add existing empires with that trait, or you get lame empires that can't build anything.

If you're just adding the borg trait, random empires will work fine, but to add empires, they must have been saved during a game that includes the borg trait.