That's something I've tried, posting my CG art to places like newgrounds/deviantart. I have not tired a proper booru yet but some booru do allow screen recording of gameplay footage (I think I found a few on derpibooru as well but only a few) so there's hope for that.
As for the live action sites, I get it, I mostly just use places like them for their hentai and eroge game content. There are nsfw lets players that exclusively play and stream porn games. So I guess you could figure out where those people stream at and try that too.