In a previous life, I sat next to the techie for the Siemens "Metal" translator suite. In their biggest production project, they took an interesting approach, which is probably applicable to any translation, not just metal or Apurtium.
They first translated from English to English.
The translation pairs put odd terms into the standard form the readers would expect, removed a large number of idioms, and in general translates "stylish" English into boring, dead-simple English.
Then and only then they translated into French and German. The result was boring but very clear French and German, with very few bizzare phrases popping up.
Some days I wish I had that language module available in my current job, to apply to legislation and caselaw...