Me and my siblings would fight all the time and get hit and stuff, zero visible injuries during and after the fight, but still quite sore.
That is to say, these girls are all guard students, sisters in arms, when you share that kind of bond it's difficult to throw a punch seriously, even in this moment I'm sure they weren't actually fighting for real, otherwise Kana-chan would have just gotten some twisted up arms with how she's posing.
So yes, for a fight between frenemies, this is pretty accurate. They want to hurt each other but they don't want to hurt each other, resulting in weak blows that have no real force or conviction behind them, held back by lingering connections and attachments to the person they are fighting.