asset store has plugins for youtube videos:
https://www.assetstore.unity3d.com/en/?stay#!/search/page=1/sortby=relevance/query=youtube
i’m pretty sure unity video player plays youtube videos also, if you pass it the actual mp4 youtube video url. (you need to extract it with those plugins, use some website api to extract it, or make your own)
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solved How to load YouTube live video streaming in unity? [closed]