This game is tagged with Female Protagonist, which I feel is a little disingenuous? But I let other games get away with it for being hot, so I suppose it's only fair.
Rogue Femme is a Slay the Spire style game (Ed: I have not played Slay the Spire) where the main draw is transformation. Each battle you win, you can choose between three cards, typically based on the enemies you just defeated, and the ratio of card types (currently Beast, Slime, and Mythic are the base types, with more in testing) determines what creature you start turning into when you're damaged.
The base game is nothing to write home about; generally you'll be either blocking or attacking, with a handful of cards that allow you to heal, draw, or enhance one of your two base types. Enemies use abilities rather than cards, and much like other games in this genre they telegraph what they're about to do, allowing you to react as best you can with the cards in your hand. Generally, individual battles won't challenge you so much as the fact that HP loss is persistent; if you want to reach the end of a map you'll want to play cautiously.
The H Content in this game is largely in events; the transformations are certainly revealing but sex does not occur in combat. Additionally, the images in this game are currently AI generated as of this writing, with plans to start introducing hand-drawn images soon. How much of a problem this is for you depends on how much AI artstyles bother you. My general rule is to be a bit more forgiving if the game design and story is good, and I can't say for sure that's the case here. The images are, at least, consistent, with a believable transition between TF stages.
The game is openly a work in progress (like many games on this site), and to the developers credit they're not rushing ahead with new levels and features but making sure what's in the game functions for the most part. There are still bugs, but few of them are gamebreaking, so it really comes down to how good what's presented is.
To be honest, I have my issues with it. Generally if you're playing this game you're here for the TF, and the TF stages being tied to losing health encourages exactly the kind of risky playstyle the game doesn't want you to have; this is probably a game that would benefit from a persistent gallery. It's also hard to strike the kind of difficulty balance I like in my games, but balancing any game, let alone a H-Game, is challenge enough.
This is really a game for people who get satisfaction from gender and species TF, and not many other people. If you're coming into this game hoping to not get feminized, you're in for a bad time. For those who do like these themes, it's not the best game you could be playing for this kind of content, but it's far from the worst.