Update to this:
On my last birthday I switched to a plan on CareFirst, which is owned by BCBS. I wrote them a very specifically worded email to see if they would cover all of the separate procedures related to my bottom surgery or if they excluded coverage for transgender healthcare. They (very enthusiastically) said that it was covered, gave me specific coverage details and pages to look at in the plan as reference, AND gave me the extension of an individual who could help me with claims if I had issues down the road.
So don't write off a provider entirely just because the internet collective says that they don't cover things. Email them. Ask specific questions about what you want. Give details that help contextualize the situation. Worst case scenario is you get a "no, we don't cover that currently", and you move on to the next provider.
If you're currently shopping, I'd strongly advise reaching out as far in advance of open enrollment as you can - they will probably be inundated with questions from people in the same boat.