I suggest to close such questions as duplicates to avoid fragmenting of content and avoiding duplicate answers.
However, in order to help users in such a situation, I also propose that we create a default procedure for such users to request translations. To this purpose, I suggest to create a meta question for translation requests. This question should be bilingual and users can post answers to request translations of existing posts from German to English or vice versa. The respective translations should be edited into the original answer.
As a prerequisite for requesting a translation there, a comment should have been left on the original post asking the author for a translation and been left unanswered for 24 hours. This is because translations by the original authors are preferrable as the original author knows best what he wanted to say and edits by other users might cause dispute. In most cases, the proposed time window should give the original author sufficient time to at least state his intentions on translating the post himself.
It would be nice if users could gain reputation for translations for translating other user’s posts (translating one’s own post could be awarded a bounty). but the only way I see to realise this with the current system would be using individual answers for the translations, which I consider to be a bad idea, since it is confusing and making questions disorganised. (If bounties were allowed on per-site metas and we would use one question per translation request, they could fascilitate this.)