Asking as someone who barely has any clue in this field: is there a way to use this for full-text search, e.g. Lucene? I know from experience that for some languages (e.g. Herew) there are no good stemmers available out of the box, so can you easily build a stemmer/lemmatizer (or even something more powerful? [1]) on top of word2vec or fastText?
[1] E.g., for each word in a document or a search string, it would generate not just its base form, but also a list of top 3 base forms that are different, but similar in meaning to this word's base form (where the meaning is inferred based on context).