You can't sell a game on Steam that uses renders made from Honey Select 2. That's like trying to sell a game that uses renders made from a modded Skyrim or Fallout 4. Steam's not gonna let that happen.
Cari has gone on record on his Discord that he doesn't like redoing/remaking stuff, so don't expect that kind of thing from him. Furthermore, he's already mentioned that he's planning to make the next game after Eternum with Honey Select 2 again, so he seems to be pretty much committed in not having his works ever grace Steam anytime soon.