That’s a difficult one. Due to their target audience, a lot of them are more focused on storytelling (usually limited gameplay and more reading along in a choose your own adventure style) for a single player. What you’re describing is a bit of an untapped market, but give F95zone.to a look and you might find something. It’s a site dedicated to collating freely available adult games (with ways to support the authors linked). It’s where a lot of the games OP talks about found their audience.
I was going to mention The Last Sovereign in this thread. It’s a little bit hard to recommend because it’s like, barely modified RPG maker sprites and some serviceable art for sex scenes, along with the difficulty. However that game is a damn magnum opus.
I just finished what exists so far for The Princess Trap last night. I have to recommend holding off on it till it’s finished so you don’t end up in as much despair as me.