Bitttymacod
Hmmm... I was under the impression that this was already the case, i.e. that if the guild was neutral that it could accept delared Kami or Karavan. It is certainly possible for a guild to be neutral wrt to Faction and civilization.
I've never been in this situation as I am a devout Karavan Tryker in a Karavan Tryker guild and I don't have any alts. :)
Unaligned homins can join any guild (even if they are marauders they can still join any guild, which makes sense—spies among us :D ). Aligned homins can only join guilds which match their alignment. Cult aligned have to join same cult aligned guilds. Civ aligned the same.
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Eldest, Order of the White Lotus