Do you guys know any manga of strong female characters, and I mean both physically and emo...

Oh, yes, yes! It's a yuri, but On a Leash has a MC fitting that description perfectly~

try this manga:

http://www.mangago.zone/read-manga/anatolia_story/

at first she's a whiny, crybaby girl. but sooner or later she will have a great character development

oof idk if this helps but I read this one manhua about a girls’ fighting school and how a boy joined it. The girls there are all super athletes, and the main girl is kinda emotionless (from what I remember).
http://www.mangago.zone/read-manga/girls_of_the_wild_s/

Thank you so much!