No, only the asker should translate their own posts. The question itself isn't the problem, it's communicating with the asker.
Once the post is translated, every other possible step of a question's lifetime could still create problems:
- Comments asking for details won't be understood or replied to
- Answers won't be understood, so the question has become useless to the OP
- The OP can no longer edit their post, as it is now in a language they don't understand. It's impossible to add new information to the question
- Should the question be closed, the OP won't know what to do in order to get it reopened
If you want to help, translating a question is not really providing that help. If someone can't communicate in the language required of everyone who joins the site, I'm afraid we can't do much for them.