Can probably rip out the engine and create new mons at least.
Take the same formulas, rename the types and statuses, come up with new things, copy moves, etc
That's my plan at least.
Would be interesting to do it with gen ai. If the author would add a suitable license, I might give that a shot.
Maybe for some inspiration, but to get a really nice metagame (potential to inspired by classic formats like gen 1/2/3), I think it'll be pretty manual to get something fun to play.