There are already characters in the MCU who are part of the LGBTQ community in the comics. For instance, Ayo from Black Panther (and most recently The Falcon and the Winter Soldier) is a lesbian in the source material.
James Gunn, who directed the Guardians of the Galaxy films, eluded to gay characters within the MCU in the past. “You know, somebody asked me will there be any gay characters in Marvel movies, and what I meant was there’s a lot of characters in the MCU and very few of them have we delved into what their sexualities are — whether it’s gay or straight or bisexual,” Gunn said.
“We don’t really know," he continued. "So, I imagine there are probably gay characters in the Marvel Universe, you know. We just don’t know who they are yet.”