Youtube video language v3 API
Not specifically for video language. You have three options that are close:
You can search by location - this will restrict the video results within a certain radius of the coordinates you specify (there's also a locationRadius parameter to configure what that radius is).
You can search by region code, which limits results to videos downloaded from a specific country.
You can search by RelevanceLanguage - this is where you put a language and rate the results based on the relevance in that language. In some cases, this works well for language-based searches, but in other cases, you may receive videos, rather than the language you specify here, which are so important that they are returned anyway (for example, if you set the relevanceLanguge to KO for Koreans and then turned on the search term "Taylor Swift", you get a mixture of Korean videos related to that term, as well as things like Vevo's music videos).
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