Yes, I've been able to make it write very well in other languages. It's ability to write good text in a language will vary greatly with the text you input. Some inputs can make it write a lot of gibberish and improper grammar, while other input will make it write properly.

You can also do things like make a characters that speak one language and another which knows both languages, then the German guy will write in German and the other can answer in English.

OpenAI recommend it for English but it generates text for other languages too (but generated text is not that good).

E.g. here is amazon.de https://imgur.com/a/5JesS3Y

I have no idea if generated recommendations are good. I don't know German. Perhaps someone who knows can comment.

I am a native german speaker. The recommendations in the screenshot are quit good and are also correct from a grammar point of view.