This is almost too easy to answer, which maybe making it hard to answer also...
The single closest thing to your requirement might be "痴女" or "nymphomaniac". The English "nympho" might not be very appetizing, but that's how it works, after the lost-in-translation factor. A woman who demonstrates pleasure or even perform action to seek pleasure is classified as borderline mental (the word "痴" connotes craziness).
Another keyword you should pay attention to is "逆", literally "Reverse". "Normally" the process of sex (often euphemized as "ecchi") involve the man imposing the activity on the woman. So if the woman would desire or take initiative during "ecchi", that's not "normal", it's almost against nature, so it is "Reverse". In J-culture, this single kanji word 逆 is used to cover all kinds of alternative or different-than-normal circumstances. But in JAV, it's a very good bet the vid involves a woman taking pro-active initiative on her libido.
Also depends on your taste, you can search on cherry-boys, boyo or various derogatory terms on the male performers, there you will surely find many vids with the female stars taking charge.
Nowadays, the pendulum has perhaps swung too far towards non-aggressive males. On so many vids and scenes that doesn't telepath its a "Reverse" theme, it turns out the male is excessively pathetic. When the woman has already taken off her top and her bra and grab the guy's hand and put it on her bare breast, for any normal man that's enough encouragement to take the next action. Say she put my right hand on her left tit, I am not going leave my left hand on my side for more than 5 seconds, I'm gonna grabbing her right tit, and I will be squeezing and touching and pinching her nipples and do all kinds of things men do with women's tits. But since the last year or so, it's as if the guy has taken a reverse-Viagra and lack any interest or motivation to engage in the "ecchi", leaving all the doing to the female performer.
I find this to be rather annoying.
