Nice to see you're dealing with the problem
The English localization is not bad at all, it's just the mix of an English UI and German Voices that's quite disturbing and destroying the atmosphere. It's also very sad, because the German translations that worked some time ago were very good and fit well into the atmosphere of this great game.
I'm sorry to be that impatient, but are there any news regarding the localization problem?
EDIT: I now redownloaded Entrenchment and I was given the choice between English, German and French. I chose German and now everything is German, except some ship sounds (e.g. the sound of the light TEC frigate) but that was the case even before the localizations "got lost".