Fediverse Usernames: User List or Directory

A lot of the people on this server have a Fediverse presence. Is there a central list anywhere that would make it possible to find everyone at their home server, so they can be followed on the Fediverse in addition to this site?

There’s no single user directory, but you may check individual account profiles for their (self-maintained) “On the Fediverse” field.

Instead of trying to follow too many people, I would recommend to subscribe to the #ActivityPub and #Fediverse tags, then selectively follow people posting there based on your interests.