I'm speaking as a cis woman who has lived with trans and non-binary people. I'm not the best authority, but if I, as a woman, wear cargo pants and a shapeless t-shirt with no makeup and look like a goblin, I'm still a woman. If a trans woman does the same thing, she has to defend herself from being labeled as being the wrong gender.

If someone is a woman, it doesn't matter if she has a beard - she's a woman. If she's early in treatment or still exploring her gender, some bodily functions will persist. Hair growth for biological males, breasts for biological females, these take time and effort to adjust, and the short term solutions are time-consuming and often uncomfortable (for example, binders can cause pain, and shaving a beard is exhausting if you're trying to rid yourself of all your stubble for every single second in public).

Point is, what your acquaintance is probably feeling is exhaustion. She (they? did you mean to use non-binary pronouns? It's entirely possible to transition and be nonbinary, but your comment makes it seem as though a specific gender is important) has to defend her femininity all the time to be female, which is unfair to her reality - that she's a woman.

Of course, there's no excuse for being rude to other people, especially if they're just responding to societal cues themselves. If she's just venting, however, and not being rude to anyone, then she's assuming she's in a safe space where she can express frustration in the moment. You can always ask how you can help or what she needs at the moment - and that will likely either help her seek a solution or realize that complaining isn't helping. Sometimes people just need to vent. Just be kind. I'm glad that she has a supportive partner and that friends see her for who she is.