Reddit does something similar now. It auto translates posts and they show up in Google in my native tongue. Really annoying since when I search in that language I specifically don't want English sites.
Thanks to the geniuses at Reddit, I now frequently find posts on /r/de or similar German subreddits translated from my native language into one I'm worse at!
It took me some minutes to realize what was happening. At first I though it was some language specific sub before too many post had strange language.
Fake culture and putting things in the a strange cultural context and trying to hide it.
Does it actually say it is somewhere obvious? My girlfriend and I both looked something up and each got the same Reddit thread, but one in English and one in Chinese. She had no idea hers was translated.
But I also thought it was supposed to do the reverse if someone comments in the translated language, adding an original-language comment instead of a translated-language one.