I think you mean language filter. Internalization often means something else
Mastodon tries to implement a language filter too, but it didn’t go very well from what I heard – false negative and false positive happen both too often.
I wouldn’t be against this feature though. IMO there should be a message confirming if the language is recognized correctly to refine the language model, but that might be diverting developers’ effort from more helpful features.
I think the ones without a word separator should be gone, because it’s harder to read