Greasy Fork is available in English.
Adds the option to export subscriptions from YouTube as an OPML file of RSS feeds.
< Feedback on Export YouTube Subscriptions to RSS OPML
Done. I've made several updates to the script since this was posted that should hopefully make it appear for you now; if not, please post on GitHub with more information.
Can you please provide a screenshot of download button? Script is running, I opened subscription list it sidebar but button doesn't seem to appear for me.