One question I have is if there should be a distinction between male-to-female trans athletes that transitioned before vs after puberty. I think if they transitioned before puberty they should definitely be able to compete alongside all other girls. If they transitioned after puberty, maybe there's an argument for not allowing it.
I think for almost every sport, anyone of any sex or gender who wants to compete with men should be allowed to.
I think intersex individuals should be free to compete with the group they identify as. Maybe there are exceptions to this that I haven't considered, but the women I've read about like Semenya, I think should be able to compete with women. It may be a competitive advantage, but I think that's okay. I don't know of an elite athlete who doesn't have physical advantages that help them be elite.