Half of us don't play sports? I was a football, basketball and hockey captain as a kid. I played American football in university. I'm a martial arts sparrer, a damn good one at that, and I played a lot of tennis. My advice at least is coming from a legit athletes perspective.
Here's the issue: I personally was actually serious about sport, you're seeing sport and the segregation of sexes the wrong way! That's why it's coming across as sexist. Yes, it's better when you're in the right team but only when you're on the same playing field. Could you play tackle at high school football level? Unless your school is particularly desperate for players; unlikely. You have to be pretty big to be tackle and we're talking muscle not all fat. Yeah, maybe it's all well and good playing pickup at the park but a competitive playing field, no chance! I played American Football in University, in a non competitive league, the only position I was any good in was tight end/receiver. I was no weakling either but guys who play tackle, they're huge!
There are lots of transgender individuals who want to be sportsmen and woman. The question you have to ask yourself is what's important to you? If you want to actually play in college, you need to be good and you need to have played competitively, so if that's what I wanted and I'm in your shoes, I'd sign up to the girls equivalent at school (I had no choice there, I was in an all girls school, so count yourself lucky there!) and get some experience and stats on my side. I know how college sports work in the US. In the UK, most sports are set up so anyone can play but college sports in the US are about the sportsmen and woman of tomorrow. Future MLB, NBA, NHL, NFL players. You're highly unlikely to be able to walk right into a college sports team of any substantial standing. And If you want to play basketball and you're not 6 foot plus, you're going to have a lot to prove and be twice as good. Something you're unlikely to achieve playing random games at the local court. Learning about teamwork and picking up plays from the coach and acting on those instructions ASAP is vital to a sports team player and to learn that, you need to be on a team. Interpreting plays and instructions immediately takes time to perfect.
People will see you as your birth sex? If you're not out at your school and transitioning, that's already the case unfortunately. And while I understand it's awkward in a female changing room, I doubt you would be comfortable in a men's locker room either right now.
I know a young lad here who was lucky enough to have great parents who blocked his puberty and he now on T. He's 16 I believe now and plays in his boys high school hockey team. But prior to transition, he did a lot of hockey and it was in mixed leagues as a very young kid and then solely girls teams growing up. For him, sport was important and playing at competitive levels meant when he went to high school and was stealth (he later came out to them) he made the team easy because he's damn good.
There's Olympic athletes who live for their sport and have to compete as birth sex until they can start hormones and get their surgery and then compete as the gender they identify.
The idea here is that transsexual athletes don't start training after transition. You need to determine what's right for you, no one else can answer that. If you legit want to play college sport and that's important to you, you need to start playing and competing regardless of the gender of the team. At the moment, pre-T, your level playing field in a girl's team. If you want to improve your game, this is where you'd best improve. Your team may not be the best, but other teams will be great and have better players. If you're the best player, you'll have the strongest opposition player guarding you and making you work hard. Possibly even two on one if your team really suck! And if you can't do that then admit gender identity is more important to you than sport and start seeing sport as something you do recreationally as opposed to something you'd do at a competitive or college level because you could potentially be setting yourself up for failure!
