It's one of the newer historical myths, like George Washington cutting down the cherry tree and owning up to it, or people thinking Christopher Columbus was insane for saying the world was round. It's even less specific in this case. The Marsha Johnson story has been very quietly retired, and is now more about generalized "black queer trans women smashing cops' heads in."

That being said, there were some unsung heroes who were black and GNC. My favorite is Lexington, KY's Sweet Evening Breeze. What was so interesting about him is that he was able to make himself a respected member of the community. In Kentucky. in the mid-20th century. I have family from there, my sister still lives there. My mother did meet him in the 60s when she went to college at UK, though she disapproves of crossdressing. She said sometimes he would dress as a man, others as a woman, and just walk down the street saying hello to people and smiling at them. Other family members have more fond memories of "Sweets."

https://nkaa.uky.edu/nkaa/items/show/2391