Maid -"Skin colour is not a social construct. Gender is. You cannot legitmately claim to be black if you are not black, IMO. You can legitimately claim to be female, whatever your biology."
That can't be right. As mammals, we are biologically male or female, irrespective of any social construct. We are male or female precisely by dint of our biology. That is why transgender people have cosmetic surgery to try to superficially mimic the sex they claim they really are. It is not their biology, which is why they have to undergo surgery or have to take synthetic hormones the other sex produces naturally.
It is not an actual transformation into a different sex. But even then, most still function sexually as males anyway. So there must be a fair bit of cognitive dissonance going on even they demand to be acknowledged as female.
The hormones taken by transgender people aren't therapeutic in the same way as hormone replacement therapy to replace a person's deficit of naturally occurring hormones.
I don't think expressed skin colour and being black or white or anything else is like a person's sex. Biological sex is clear cut into male and female. Actually because of this there would be more justification and many more factors for people to identify with others in different ways along the blurred lines of 'race'.
I guess, someone with white/pink skin using tanning products is the similar cosmetic alteration of skin colour is an example. However, I don't think if you used a lot of it, you would claim to be black by virtue of that cosmetic or chemical alteration (there are tanning tablets, I think).
If you stop using tanning products, your appearance will revert to your natural colour. Barring issues like disease/liver trouble, etc.
If Rachel Dolezal, used fake tanning methods, she is like many white people. But they don't claim to be black by virtue of that. Unlike men who put fake boobs etc. on/in and pronounce themselves female by virtue of that, while still bizarrely remaining as fully functioning males. Even if they weren't, they would still be male, biologically.