I will add gender doesn't equal sex. Biological traits may be associated with sex but gender is not sex. Some cultures don't even associate gender with physical traits at all. Race is a physical trait. It cannot be changed.
Heres examples of such cultures...from
https://nonbinary.wiki/wiki/Gender_designation_in_different_cultures
The Dayak are a farming community in West Borneo. When anthropologist Christine Helliwell visited, she described how the community did not know how to define her gender, "despite her female body."
[1] She writes:
"Gerai people remained very uncertain about my gender for some time after I arrived in the community... This was despite the fact that people in the community knew from my first few days with them both that I had breasts (this was obvious when the sarong that I worse clung to my body while I bathed in the river) and that I have a vulva rather than a penis and testicles (this was obvious from my trips to defecate or urinate in the small stream used for that purpose, when literally dozens of people would line the banks to observe whether I performed these functions differently from them). As someone said to me at a later point, 'Yes, I saw that you had a vulva, but I thought that Western men might be different.'"[1]
The Dayak associate expertise, not sex, with being a man or woman. To them,"[a] 'woman' is a person who knows how to distinguish types of rice, store them correctly, and choose among them for different uses."
[1] As Helliwell learned more about rice, "she became 'more and more of a woman' in their eyes."
[1] Her gender still remained ambiguous, however, because she never gained the expertise of even a girl in the community.
The Hau are a community in New Guinea. To them, masculinity and femininity wax and wane as someone ages. Children are not born as men or women and are not recognized as such until puberty. From then on, each son a woman bears increases her masculinity and each son a father sires decreases his masculinity. By the time Hau become elders, they are once again genderless.
[1
The Lovedu are a community in Zambia. They assign gender by social status instead of biological sex. Higher ranking people are considered men. A high-ranking female could even marry a young, lower-ranking woman and be considered the father of their children. The biological father in this case would be one of the lower-ranking women's lovers
My point is transgender is a social identity. There may be biological edvience for why one may be trans but it's a cultural thing due to it being gender which is based on how you feel not your body not sex which is a social construct based physical traits. But race is a physical trait. A construct yes but based physical traits