It is scarcely possible to confine the range in where a question is a general reference. There will always be some questions that are on the brink. On top of that, everyone will have a different opinion of what is on-topic or off-topic.
We have to consider different cases of translations request.
Asking for colloquial words or dialects
I think this is not easy to define for a non-native. Of course, Duden often mentions the usage. A good question would contain the translation you expect and outlining your thoughts. But even if not, a trivial translation for one of those would be on-topic.
Asking for idioms, figurative meaning, etc.
These question should be always on-topic, though you can find explanation to those idioms that are used often. For most idioms, non-natives are not able to recognize the meaning and we shouldn't discuss which one are easy to understand and which aren't.
Asking for an unusual word
Here I put neologism, slang, rare used words etc. together. You will only find a couple of sources and most of them are very rudimentary. On-topic.
Asking for word-choice
If you're asking for the best word in a special context, it is on-topic. Again: Non-natives don't have the feeling to choose the right word. Best practice would be to mention your best guess to show that you had thought about it before you asked.
This is also valid for synonym requests to a word in given context.
Asking for any translation for a word, sentence, ...
Off-topic, if it does not fits into one of the previous groups.
Note: It's likely that my list in incomplete. But for now, I don't come up with any more.
Regarding the question, why you post this one:
It is off-topic, because he is asking for any possible translation, giving no context or nothing else. I could give about 50 possible translations for this sentence. Some are good, and some are not. Anyway.