You might want to browse through the entries in the Weekly Flag Challenge over the years (although it seems to be defunct now, unfortunately*). Here's the wiki page: https://www.alternatehistory.com/wi...ate_history:weekly_flag_challenge_contestantsI'd like to see people's favourite flags you didn't make from other people's timelines.
*(Yes, this might seem like a bid for some interest in getting it restarted; I plead guilty, though I'll admit I am a bit biased, having taken part in it for a while and even won a Turtledove as a result.)