Last I checked, women could be evil, megalomaniacal, narcassistic and sadistic. The triad of "narcassistic, sadistic and megalomaniacal" is in fact a very common villain trope, particularly in the action genre, for men as well. Look at Hanz Gruber from Die Hard and you will see he exhibits all of these traits strongly.

As to how you physically present her, you could go either way. If you want her to be wearing heels and a slinky red dress, go for it. That's an iconic, villainous look, just like dudes running around in sleek Italian suits with slick backed hair (not the most practical getup to fight in either). If you want her to fight in heels, go for it. No, it's not realistic, but neither is pummeling your way through 5000 guys with your bare hands over the course of a couple hours. If you want her attire to be more practical, it can be. Maybe she struts on screen and kicks her heels off before beating the crap out of the protagonist. Maybe she's not walking at all, or she has a gun, who knows?

I doubt this would be something that harms sales.