I have to adapt a branded document for a one-off Arabic translation, but I have no idea how to choose an Arabic font since I know almost nothing about the language or cultural considerations that effect typeface connotations and it has letterforms that are very different from English. I know this may be a somewhat subjective question (so I understand if it is closed), but there must be some guidelines for working with fonts in other languages.
I, personally, would pass on the work explaining a native language speaker would be needed.
While I have done some translations into languages I do not speak or write (Spanish, Italian, French, German, Russian), I would not be comfortable when the written language is so vastly different. And much like I would not even attempt to rework a piece for Chinese or Japanese markets due to the vastly different letterforms and cultural connotations associated with them, I'd feel the same about Arabic.
It's one thing to rework a translated text when the reading direction is still L2R and the letter forms are still essentially Roman. And it's merely the sentence structure which may be changing. Even if you don't speak a language, if the letterforms are still Roman you can still choose fonts, weights, placement, etc relatively easily. But once you go beyond L2R Roman (or even Cyrillic) alphabets.... it really takes a native speaker/writer.
The only possible way I see this working well is to work closely with a native speaker so they can continually inform you of any social and cultural connotations a design may be conveying. Such a native speaker may also be in a position to suggest some font usage which is "standard" or "common" in that language. I realize some clients simply won't be vested enough to consider all the pitfalls which may happen. In fact, I'd hazard most aren't and merely will want you to "make it happen".
For this reason I'd politely refuse the translation work and offer to provide any unique design elements from the original piece (for a fee if appropriate), such as photos/logos/illustrations, so that someone else could work on the translation.
Of course, if your position is one of employment and you aren't in a position to "pass" on the work. You would need, at a minimum, to hire someone who speaks the language - even as a temp worker or on a freelance basis. Whoever did the text translation may be in a position to help you with layout as well. Anything less than that would merely be a waste of time, and the client's/boss' money.