Hi ! Thanks for the game :) Here are my thoughts (I played the 1 player mode)
The thing that annoyed me the most is the camera. I think it was moving too much and following both characters too much for a versus fighting game. I would have prefered the camera to always focus at the center of the screen, so that you can always know where you are and at which distance you are from losing, and it would not be bothering while trying to hit the enemy because hitboxes are pretty punishing. You can still keep some camera motion whenever one of the girls is going to lose to put the emphasis on it, but I believe it should stay immobile during the overall fight.
As I mentioned, I had LOT of trouble with hitboxes. I felt like I really had to press the input at the perfect frame, else the AI would just kick me again and again and it felt frustrating. Also, I did not really understand how the different attack heights work (I believe it was depending on the joystick angle but it didn't feel really responsive), and I'm not sure it has a real gameplay impact, other than kicking the opponent higher and further, so I was just using the high kick at some point since it seemed to be the most useful attack. Maybe you could make the high kick make the target get bumped higher, and the normal kick being pushed away further, to get some balance. Sorry if the attack terms are not correct according to taekwondo :p
It seems the AI could move while being airborne, making it come back like 2-3 times after I clearly kicked it out of the ring. It would have been better, I think, to kick it less far, but disallow any movement while airborne, since it would seem more intuitive and less punishing. And last small detail about the AI, it selected the same character as I did during my first fight. I suppose you can do that in a 2 players game, but I was excepting it to pick another one, to help me making the difference between the fighters.
Last negative thing I wanted to mention is just that the fight intro sequence takes way too long, and it feels long mostly because nothing is happening on screen.
Other than that, the kick feeling is nice and clearly polished, which is great since that is basically the only thing you're doing, and I wish I could spam it a little bit more because I liked kicking my opponent :p The artstyle is nice and very efficient, it has a Nidhogg vibe and I like it a lot !
I'll play the 2 players mode when possible, because I feel this is made to be played by 2 people and not against the computer ! Great job overall :)