How important is being an RPG in this case? (as I note only a couple of your examples are in that genre)

The below suggestions are not RPGs, but I think fit your request.

It's a survival game, but Conan Exiles ticks a lot of those boxes once you get a bit geared (which doesn't take super long), and it can be played single player. Just have to be okay with some janky experiences.

I will also note that you are a girl in Hades 2.

Sifu is another one you might enjoy, though bosses certainly are a challenge.

Bayonetta is probably the most pure example of a horde-fighting action game with a sexy female witch protagonist. Lollipop Chainsaw is there too, for more of an airhead protagonist. Darksiders 3 could fit the bill as well.