Different organizations will have different conventions about this. Your org and office might have to figure out what conventions it wants.
And, as an individual (especially if your office is in China?) you might want to consider how much Mandarin you're able to learn, even if only for goodwill but years from being able to follow engineering conversations.
Related thoughts...
A friend mentioned getting into an elevator in the US, where two people were speaking German, and they switched to English as soon as they noticed him, even though they were strangers and not talking with him.
As someone who's worked at multinational companies (one Chinese, one Japanese) while based in the US, I've felt humbled by colleagues' impressive efforts with English.
One place, there were times I was in a meeting of team leads and the director, and I was the only person who was a native English speaker, and everyone else shared a different native language, yet everyone was speaking English, though some not fluent. (Defaulting to English was by convention, not only because I was there.)
Although admiring colleagues' language abilities (and the progress of some over time prompted the thought that one day that engineering lead might be running an international company), I sometimes felt a little bad that some of them had additional language burden atop technical engineering work. A consolation I imagined was that maybe some of them wanted to practice English.
At one multinational, I encouraged specific uses of written English engineering and product management communication. Which, in addition to the usual benefits, helped by it being easier to read&write across language frictions, than to hear&speak. And some meetings were converted to be country-specific, in whatever language people communicated most efficiently and comfortably, so long as we could stay in sync (asynchronously) via effective documentation.