Many feminist do advocate for men's rights. The thing is that they rarely get credit for that. And that what we understand by men's rights might not be what men want.

For example, many feminist are asking for paternity leave equal to maternity leave (in my country is 4 paid months). But the men who acuse them of misandrist, are angry and claim misandry because they don't care about paternity leave, but think that affirmative consent in sex is "going too far" and that now "women would falsely acuse them of rape" despite evidence on the contrary. They are also angry about domestique violence laws, but against teaching boys things they deem "womanly". Even if that skills come handy when you live on your own.

My point is that many times, if you bother to read what feminist are actually saying, you might find that there is a willing misinterpretation of what they say. Now some people call hypocrites feminist for not saying anything about Afganistan, even if they are actually saying things about Afganistan in their social media under different hagstags (not #metoo because it won't make sense).

So chances are that the feminist that support trans people, are using trans hagstags to do that and you are not counting them as feminist.

TERF are a problem (big one), but that doesn't change that #metoo applied to trans women too (and chances are that even more, since the more vulnerable, the more risk of suffering abuses). And same with other traditional feminist topics like equal pay. On the other hand, body integrity and pro-choice, include transmen. After all, if they can get pregnant, they need the right to choose. So whenever feminist ask for safe abortion, they are in fact fighting for men's rights (in this case trans men).

At least this is how I see it.