Yes, I did a total of over 100 stamp and visa translations. I had to translate "entry/exits" from Cantonese as an example, Turkish too even though they were accompanied by the English equivalent (for the ones from China) and pretty self explanatory from Turkey, but still we agreed on the phone with the agent that it would be much better to be prepared than to be sorry. There are no specific rules around it (apart from "everything non-English or French has to be translated") and is solely at the discretion of the officer. Some take this requirement mildly, others might require more. Take it straight: think of yourself as someone who knows only English/French, but at the same time didn't grow in isolation to be able to understand that Munchen in English would be Munich and thus is self-explanatory, Arabic, Mandarin, Cantonese, Japanese, Russian and the like use different alphabets and thus need a translation. Worked for me, worked for most