Can you take a pair of offset jaws off and just flip them to make a closed jaw

Might not fit right. In the past trappers, took REGULAR jaws out of some traps and made offset jaws not sure what would happen using your idea.
Might as well try in on ONE TRAP and see. IF you are a welder, some guys cut the base plate and disassembled the trap, re-positioned the trap jaws
then welded the base back up...usually adding a base plate with d-ring.

You'll still have an offset with most jaw designs. It just won't be as aggressive as the factory offsets but ateast the pinch part of the offset will be gone. Not sure what would happen if you had lugged offset traps though..

I was just curious I mainly water trap but a buddy has some old traps I’m supposed to get. There all offset looks like I will just order some new jaws

Try turning one around. Might surprise you what you come up.with.