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I was able to change language by clicking on the gear icon in the web player (bottom right).

For whatever reason latest Chrome and FF on MacOS does not have any settings/gear icon ¯\_(ツ)_/¯ .

Strange, Chrome on MacOS shows it here. Ugly workaround, you could download the video and select the appropriate audio track in your video player.

Weird, I'm on Firefox on Windows and it's there.