Why not use language detection? TextBlob and Polyglot come to mind.
https://textblob.readthedocs.io/en/dev/api_reference.html#textblob.blob.BaseBlob.detect_language
Today we talked about search note15djknj3kh6szcj82pp6sm98vk3pw40fg8ajsx8mrpfg3zadyeqhqfmsl2n, what about language filtering (that can be a search params, too)? Nostr now is english centric, but with the progressive expansion a language filter will help newcomers to discover new content and raise the signal-noise ratio.
I found this PR about the matter https://github.com/nostr-protocol/nips/pull/182 by #[0] and I think the tag is the right approach, because can be used on other kind types, if needed.
Ideas?