That aside, the tag villainess is more for the flair, the aesthetics, and the genre. But as you might know, you actually never ever see a real villainess in all the villainess stories.
They are mostly heroines under a different name who often end up selling fashion accessories, bakery goods, and soap to the fantasy world. And the obligatory break-up of an arranged marriage.
If I write a fanfic, I am writing one where Geralt saves the girl and she grows up to be the big, strong princess-mage she was destined to be. And is cute and frilly the whole way.
I have two works, one a fanfic, the other an original. The MC is essentially the same as is her personality. But the environment is different, so her personality shows different aspects.
The classic, woman does x in novel = arrogant stuck up green tea bitch. Male wannabe hero does same x = somehow still respectable member of society. ???????
Sometimes, it isn't about what they do, but how they do it. It's why you can't really swip-swap men and women in certain roles without making other adjustments.