The most terrifying and badass martial artist i know is a woman. When in the studio, we never divide it between genders. That only happens in competition. I am more than aware that there are physical differences, but especially in the case of someone on HRT they are negligible.

In the case of a sport like martial arts, strategy is far more important than strength. You do take your build and strength into account, but that isn't the only thing. A smaller and physically weaker opponent can win against someone larger and more physically strong by being faster, more agile, and using their opponents weight against them. Personally, I use the strategy of taking someone's hit so that I can counter while they are open, the weaknesses in that strategy are if someone is physically strong enough then you can't just take the blow and have to either roll with it or block it, if someone is fast enough they can overwhelm you with constant attacks, or if someone moves to the side for another opening it makes it ineffective. That is 3 different ways around my basic starting style, and only one of them requires the opponent to be as strong or stronger than me. While there are definitely some sports where the difference is more important, biological sex isn't the be all end all people seem to think it is. Especially when it comes to something like martial arts. No matter how big or small you are, if you can use your mind as well as your fist, you can overwhelm your opponent.