The Real Strong girls: kick-ass action female leads/warriors

shounen, a little bit harem-ish, supernatural fantasy.
female warrior, swordsman.
2nd female lead: high school girl mage
amazing manga with a compelling story. a definite read.

webtoon shounen romance.
female fighter. female lead is kickboxer, the reigning champion, multiple titles.
✼ harem. battle school for girls recently made co-ed. fight for love! lol.
A harem without being outright ecchi. props for zhena for that. there's more to the first girl than what meets the eye.

seinen
Assassin/s
a young girl who was secretly developed (and removed memories) to be a living, breathing weapon of destruction and the story of the people in their 'institution'.

shounen, two main characters. girl (medaka) and boy
female fighter, martial arts/magic
✼ harem, ecchi, battle school.
my favourite mary-stu girl. ever. of all the girls in this list she's probably the strongest.

manhwa shoujo
female swordsman, kumdo (or kendo in japanese) practitioner
✼ epic fantasy adventure, inter-dimension travel.
lena. every woman's girl-crush (and men too), hahaha. girl with a crappy life gets transported into a mediaval world and had her worth recognized there. also got an auto-upgrade in skills upon crossing worlds as the child of destiny. time for a tough real-life grinding (game-speak lol) for lena that even men would find difficult.

#shoujo c-webtoon.
#physically strong girl.
#mistaken identity. Handsome girl is now branded as the heroic MALE student and it's only the first day of her transfer. The reason for transfer is his crush, braving the southern area alone. Actually, she's like the big boss of the gangs in their northern area.