If you want to join a clan in ZOぞ, this guide will turn out to be helpful for you. Just follow the step-by-step instructions to join a clan.
You will need to join the ZO discord server first.
Just join and verify, then go to the channel #rules and info.
After that, you have to join the ZANTETSU discord server.
Go to #recruitment to join a clan; you must pass a tryout.
These are all clans!