Can we change the rules a bit and then run the engine. How well would it work?

[ARNAV69420]

So, lets say we wanted to implement Three-Check Chess with some changes in the rules like say pawns can move diagonally. Would this be possible to do this using this engine? Like Stock fish supports some variants. Does this engine also support user variants. If so How should be go about it? Would changing just the rules suffice?