Also my use case includes more than 20 languages. To find usable embeddings for all languages is next to impossible. However, there are keyword plugins for most languages in Solr or ElasticSearch.
Btw. In my benchmarks the result look something like this in English (MAP=mean average precision):
BM25(keyword search) -> MAP=45%
Embedding (Ada-002) -> MAP=49%
Hybrid (BM25 + Embedding) -> MAP=57%
Hybrid (Embedding + BM25) -> MAP=57%
And that's before you use synonym dictionaries for keyword searches.
If you make the embedding with an LLM, it should work for any language the LLM is trained on.
For my tests, I used Ada-002. As data I used small news articles and no chunking and no preprocessing. The query for the articles is embedded directly.
Of course, improvements can be done for both approaches. That should just exemplify, what you might expect with hybrid search.