I'm in France, but my Google, browsers and devices languages are English. So Youtube randomly auto-dubs (and auto-translates the title of) some French videos into English, and some English videos into French. But they're never the same videos depending on the devices or the browsers. However, the automatic subtitles during the preview remain in the original langage.
Do note that when rolling out features like these, they geoblock them, even on a per run basis, so it might be happening a lot throughout the world but it just hasn't reached your country. For an example, mobile YouTube in the US lets me minimize the video and multitask while still seeing a picture-in-picture window and the audio, while as soon as one lands on France that feature gets immediately disabled.
I've heard about different features in different regions, but GP is also in France.
I am also not connected to my account when I browse in Edge (it's my work PC, it also uses a separate IP), so I don't think it's related to the feature being rolled out on a per-account basis.
I'm in France, my devices are set to en-GB, I've watched only English videos (plus the odd French one) yet youtube decides to auto translate audio in German and lately in Spanish.
