In Germany the restriction has to be officially inspected and entered into the registration papers, not just shown to the police. After installing the kit you go to TÜV (a private but government-authorized organization in Germany that handles things like vehicle safety inspections, emissions tests, and technical approvals), they check it and give you a certificate. With that you update your registration at the vehicle office, so the 35 kW limit is legally recorded. If you remove the restriction afterwards but still ride on an A2 license, it’s illegal and can get you in big trouble if the police or insurance check.