I spawn some white legs and great khans and they shoot each other. Then I reload the save to record the rematch but all they do is aim at each other. Only the melee guys fight. I have to wait 24 hours and come back before everyone starts shooting again.

Don't have that many mods -
Imaginator.
Better performance for older pc's.
Liberty Prime.
Imaginator
And a few other mods I've created that makes them fight one another.