I apologize if my report is not clear in places as I only have 7-ish hours in this game.
I tried swapping a Precision Assault Rifle with a Heavy Assault Cannon, both already equipped and not in my inventory, just as the subject says I dragged the Heavy Assault Cannon on top of the Precision Assault Rifle, and the game crashed, I attached both the crash log and my latest save, it was an autosave