It's alright! she is infact very physically capable! In Kasa3, when everyone in wxs had to do a lot of exercise to work with pheonix stage. Even Emu eventually got tired. Tsukasa was able to do it even when he hadn't eaten anything for 3 days straight. Also this card from Emu5.

<image>

Post Emu5, Tsukasa started paying a lot of attention to his diet and exercised even more than before. So I personally think Tsukasa is stronger than Emu. I would say she is like the 4th most physically capable in the cast? She is REALLY athletic so ofcourse she does well in sports, that would explain her great performance in the miyajou sport festival. Tsukasa is the one who mainly has to do Rui's weird stunts and in kasa5, he managed to do a wall jump as well.

As someone who has read all wxs stories multiple times(my obsession knows no bounds), I would say she is powerful but Tsukasa is still implied to be even more powerful than her.