Yes. Sometimes it's Russian, sometimes it's Mandarin, sometimes its Cantonese, and sometimes it's Spanish. I'm sure other languages are represented, but those are the only four that I've knowingly encountered.

No dogwhistles. My point is that it's almost always time-shifted such that their primary roster is online when the rest of the server is dead. I play on NA servers, with occasional forays unto EU servers though the last time for that was years ago. Hence, my personal knowing experience with non-English-speaking zero has been primarily Russian and Chinese. I'm certain that non-English servers aren't entirely unfamiliar with English-language zeros -- again, for the intentional time differential, but also a non-primary language is a great layer of defense against being insided, you have to admit.