[tscs37]

A postal box/postfach is not sufficient and that will definitely earn you a C&D. Don't do that. (21. Juli 2016, Az. 1 HK O 168/16 for reference).

The imprint requires an address that permits receiving legal notices (ladungsfähig), ie, an Address where you as a person can be found.

[kuschku]

That's relatively recent then, but annoying.

In that case, shouldn't the trick via a UG (Haftungsbeschränkt) still work?

[tscs37]

Well, even an UG (Hb) needs a business address which you will have to put in the imprint and to my knowledge you can't put a PO box as business address in the register.