The ErgoDox EZ is a wonderful keyboard, and you can get one with blanks, and reprogram the layout to support whatever language you want. The QMK repo has plenty of german layout examples, both QWERTY and others, so you don't even have to come up with a layout yoursef if you don't want to. Worst case, you'll start with one closer to your desires. Both the keyboard and the firmware are solid, I can only recommend it. Been using one at home, another at work for the past year or so, for English, Hungarian, and lots of programming, there's plenty of keys to support these. Mind you, as I write Hungarian less often, I put the Hungarian symbols on a separate layer (layers are a very powerful feature, by the way, though it takes a bit of time to get used to using them).
If you don't want blanks, and would prefer labels, it is possible to buy caps, though they aren't going to be cheap. I just went with blanks.