It's been quite a few years since I read WWI poetry, but here's a handy list of some of the best-known poets:

https://www.gaystarnews.com/article/all-the-greatest-first-world-war-poets-were-queer-and-its-time-to-remember-them/

Though I should add that history writers are all too ready to lump romantic friendship and gay love together. Which annoys me, I say as a person who lives with a platonic companion; I feel as though *my* people's history is being subsumed. But I think it's fair to say that both types of relationships are queer by present-day standards, so enjoy!