well, what do you want a guild for?
Do you just want to chat and hang out with other solo players?
has a guild called real whom has mostly solo players and it's own discord which is quite regularly used
If you're looking to start out in 1-MQ group climbs, i suggest just joining the level 1 groups, presuming you have a vault with all your gear needed to go 1-55 stored in it (see guide:
https://forums.d2jsp.org/topic.php?t=82759999&f=74 ) eventually 1 of the guilds will pick you up if you're active throughout the climb