>>47132562Someone already did, yeah. There's even a patch for it. I only asked because I was dabbling with Skytemple and saw it.
Adding in new Pokemon is also not too terribly important to me if I ever made a hack, as outside of miscellaneous enemies I would have nowhere to put them. You wouldn't really be able to play as them much unless I also applied CTC which isn't what I'm aiming for. Spriting all the Pokemon is also a ways off even if it is essentially crowdsourced right now.