So when I go to https://lemmyverse.net/communities and search for let’s say Wordpress communities, I can see at least 3 there. When I search on my instance, so I can join and subscribe, I can’t see any. Why is that? The instances they are on are not defederated from my instace.

This is what works for me:
https://lemmyverse.net/communitiesfor "wordpress!wordpress@lemmy.world!wordpress@lemmy.world)subscribebutton.There’s probably a quicker way to doing this, as it seems like it takes about 3-4 times the number of clicks you should need, but it might just be the nature of federated blah blahs.