I'd be all for creating a LGBT clan actually... but I'm not aware of any. Join a clan whose concept you like, or support your country clan like I did. Whatever feels best.
Like I'm 100% for one and probably would be a great idea. I've known a number of LGBTQ+ people on WL that probably would have at least dropped an alt in it, idk.
However, in 2017, being gay myself and hoping to build a network of people from the LGBT community on Warzone, I had set up a circle of 8 members on the [Lynx] Discord server. Five of them were from 101st! I have very fond memories of our discussions there. Unfortunately, all but two of the original 8 members retired from the game. I was part of those who retired, so the circle was unofficially disbanded.
@mat I've been in a number of clans. Sexuality almost never came up, but nobody cared when people mentioned they were gay, etc.. If you join a decent/non-toxic clan, you should be fine imho.