I’ve been on estrogen about half as long as Jessica (npub1gae…gc59) at this point, and I’ve gone from a men’s 8.5/9 to a women’s 8.5/9. It seems to be length and width for me too. Something about the ligaments contracting I guess?
It’s definitely not universal though, which is why shoemakers with > size 13W are so desperately sought after.