Back to the question: with patience, better than average skills in both languages, the file with the original English text in it and a dev that is interested to have a translation of his game.
I would believe that are quit a few, because a (good) translation help to gain a broader audience. Even if not a translation mod is also an option, but is a little more work than otherwise.
And for program that could do this Mister Google tranlator, a bad one is better than none? Or IBM Watson, I assume, but it is most likely difficult to persuade IBM to have Watson participate in this.
And no, none free house German translation for lazy people
