I dont know if this was made or brought up already, I know Leek Duck has a thing but it hasn’t been successful for me. Didn’t find a dedicated channel for this sort of thing where people can group up and get different patterns (or in my case; shiny hunt for every pattern) or at least add each other in pogo for specific postcards.
#Pokemon S/V Vivillon Hunting
lime ermine
outer flume
#pogo_friend_codes resolves the latter part
#1040555642668199936 probably your best bet for making/finding lobbies for vivillon shiny hunts (I believe there was a big thread for it at some point, idk how activity is now tho)