I may have read too much into the fact that your post was replying to a post that plainly stated that hentai games are not going to be in Smash.
But I am trying to make a distinction between "game with sexual themes" and "game defined by erotic content." Bayonetta does, undeniably, have sexual themes; however, it is primarily defined as an action hack-and-slash game. Conversely, the eroge genre is defined as "a visual novel game with erotic content."
To put it another way, Bayonetta is rated M by the ESRB and D by CERO, both indicating adult content. There is also, however, a rating above both of these for both rating systems. I strongly believe that any ESRB AO rated games or CERO Z rated games will not be in Smash in any form.
To be clear, I know very little about Fates, and I'm not arguing specifically on the merits of that game's inclusion.
If I misunderstood you, and you agree on the point that explicit games aren't making their way to Smash any time soon, then I apologize for the misunderstanding.
Again, Bayonetta is most definitely an explicit game and again, Nintendo promoted her in freaking Playboy. So Nintendo actually promoted the sexual part of the character, and her mannerisms is all about playing up the sexy in Smash too. They just barely got away with not moving up the rating for her DLC, so she's extremely lucky CERO was okay with her. But she's not a good example of "being okay". She's actually close enough to going overboard in Smash. Palutena also had some pretty unfortunate things, like her pole-dancing taunt. CERO's issue is that it doesn't care about cleavage/breast size, but about panty shots. Nintendo doesn't care as much about sexual content as you think they do. They just have to tone down only certain aspects. Also, what Osby said. You're overall worrying about nothing. Hentai Games obviously won't be considered, and it's not related to the rating. Eregos are about gameplay(and they having sexual content doesn't much matter, since an Eroge just means it has sexual content alone, not that it actually is constantly about sex-related gameplay, which is a different thing. Those are actual Hentai Games. A different genre to begin with).
It being an eroge won't make a difference either way if the content is usable in the first place. There's zero tangible difference in terms of sexual content with your general Eroge(completely different from a hentai game, which is only about the sex, not just has some sexual content) and Bayonetta, which is heavily a sexual content game that is a hack and slash genre. The difference is pretty much... irrelevant, since they're both about massive sexual content anyway. If the sexual content mattered, Bayonetta would've most definitely not gotten in.
Fate is a good example of what started as an eroge, still had sexual content within the series here or there, and is a visual novel first and foremost(and people still think it wouldn't get in because of a single game poorly being made... which was retconned anyway). That said, it'd easily get a character if Nintendo finds anyone interesting among the latest stuff(like Grand/Order) or otherwise. Not like they need to be on a Nintendo system anyway. That's something Sakurai takes into consideration, but was never a rule. Nintendo is odd, cause they suggested a character and a franchise who had zero Nintendo appearances until way later(Persona), so it might be more of a case where they don't care if they have a Nintendo game, but if they can get the series on Nintendo, it's a good business decision(which fits Joker pretty well. And that's if it had any bit of relation to why he got in. There's nothing to suggest it was related. And no, SMT doesn't count as they're different series that only have some related stuff and some crossovers. Persona and SMT are officially separated series according to Atlus. Besides that, if SMT was important... why does it have zero content in Smash? Even Final Fantasy VII had something beyond it, even if it's just literally the Chocobo Costume, labeled as general Final Fantasy and coming from a spin-off game).
I also see where the confusion is; H-Game is just another name for Eroge. I mean that porn games(which is the other genre I meant, just I worded it wrong) won't be considered. H-Games/Eroges are basically just R-Rated films in terms of their content... which is basically what Bayonetta would be in terms of ratings. This is why I don't see them being ignored due to their genre, just if the particular game literally has nothing to do work with instead. Since gameplay is the key to whether a moveset can be made or not these days. Only a tiny few characters actually had to have a lot of stuff made up, and it's actually rare where their own regular gameplay wasn't adapted at all. Star Fox might seem made up, but some of the stuff actually is based upon the series. Fox being fast, for instance, is due to being in a fast Arwing. His Laser is pretty clearly the same one the Arwing uses. Later on, he gets a new Side B that is pretty much the Boost move. So still mostly made up, but some basis(he's also on the ground in the N64 multiplayer with an actual weapon too). Captain Falcon is practically 100% original, using Japanese Superheroes as his basis. At most, his speed is pretty much the point behind F-Zero, if anything can be looked at from the games. There's still some moves heavily modified(like Monado Arts), but it isn't done that much nowadays. So yeah, if there's worthwihle gameplay that can be adapted, it's not hard to get a character, imo. There's going to be other factors(like licensing, the game is way too obscure or has zero translations, etc). But generally, I don't treat a genre as a major downside on its own.