I've seen a few european instances that are completely irrelevant to me and in a different language and I'd prefer not to have them cuttering thinga up
Is not possible as of yet. The only solution is to defederate.
For now the only option is to block every community that you don't want to be seen individually. It is on the to-do list of the Lemmy devs though. But don't expect it in the near future.
I had similar problem and want to block all communities from specific instance (lemmygrad to be precise). I used community search by instance name and block them one by one.
It would be great to be able to select all results and block with one close click.
Would love to know how to do this. My feed is full of German and Korean if I choose all. I'd love to be able to avoid seeing posts in other languages I don't speak or read.