Translation:How do you translate this sentence?
As an ethnic Chinese and native English speaker, I think both are fine. Your example can be used as an open-ended question addressed to many people. The answer on the other hands is directed specifically to 1 person the subject is talking to (you/你). I am not sure if there are differences between the colloquial usage in China and Taiwan but kudos on your ability to read and write traditional Chinese!
So, in Chinese, does 你 refer JUST to the specific person being addressed, and not to any person in general (like it can be in English)? (For example, in English you can say "You shouldn't judge a book by its cover", which can be re-worded as "A person (anyone) shouldn't judge a book by its cover")
Well, 這個句子怎麼翻譯 & 你怎麼翻譯這個句子 are both natural and correct, but used in different situation.
The 1st one I will translate "How to translate it". The second, I'd like to translate "How do you translate it." I don't know do they mean different in English, but in Chinese, I consider it's different.