I don't know what StVZO means (I only the TUV in Germany) but I don't think you will get through the "APK" with them, doesn't have to be a problem though just mount your stock lights when you go to the APK.
I don't know if it will attract many cops but since there are tons of of altezza's on the road and strange looking blue, purple and whatever lights for VW's I don't think you will have much trouble with the cops.
But 100% legal, I don't think so
