These questions are supposed to help not only the original asker, but also anyone who happens to google upon the site or ask a duplicate question. This means that an answer that uses the asker's mother tongue, e.g. by suggesting such a translation, might not be desirable. On the other hand, such parallells could enhance an otherwise good answer.
Which best practice should we adopt?
As an example, if I were to ask what gemütlich means, would it be appropriate to reply that a Swedish direct translation is mysig?