trans kids playing sports is an incredibly easy test of principle. do you believe that trans people have a right to live their lives as fully and freely as everyone else? it's a "yes" or a "no". everything after that is a distraction.
I watched this show during the dark ages, so I remember that the conceit was that this girl dressed this way solely to fit in with the nerdy crew bc they admired her so much and, really, that's a normal thing for a twelve year old girl to do.