I need a Rom-Com recommendation. It can be actually anything, doesn't matter if japanese or korean or taiwanese and so on but I already watched most korean so maybe japanese would be better... I want kind of ... plaful kiss, boys over flowers or you're beautiful (Not the japanese versions please, I already watched them XD) Just school theme or just young people. I would be sooo happy if you could help me!
Japan: Kimi wa Petto (not school theme, but one of the leads is young. :) ), Mei-chan no Shitsuji (involves an elite school that also has butlers), Nodame Cantabile (they are in college), Otomen (really cute high school drama), Q10 (another cute high school drama with sci-fi elements).

Taiwan: I Want to Become a Hard Persimmon (high school romance), Momo Love (another highschool rom-com that fits your request).

I hope that helps!
I think that you already watched all the rom-com japanese dramas that fit your criteria. But here are some Taiwanese that I think you may like:
Devil Beside you
ToGetHer
Momo Love

All of them rom-com, all have a school enviroment. Probably Devil Beside You is more like what you are looking for.
Hana Kimi (2007) It Started With A Kiss Ma Boy Ouran Highschool Host Club Devil Beside You