I've researched it some, though I'm old school and hunt Schwarzwild (Wildboar) in the traditional ways. As far as I know the old standard of shooting hours being an hour and a half after sunset, an hour and a half before sunrise still applies. But the authorities have turned a blind eye to this restriction for Boar hunting for decades. This restriction may have changed for Schwarzwild, depends on the state and local authorities.

There are U.S. export restrictions and German import restrictions. They seem to change periodically. Even pixel restrictions on thermal cameras.

FLIR cameras might be your best bet or a Thermal monocular.

Pulsar makes an interesting attachment for a rifle scope, obviously designed to withstand recoil pulses.

It is my understanding the restrictions are to try and keep the technology out of the hands of unauthorized foreign fighting forces.

IMO thermal sights for night ( or dim light) Boar hunting is a safety issue. You can much better see if there is anything behind the Boar that may be in danger of a miss or passthrough shot.

Probably the easiest way would be to check out what you want and see if Amazon will ship it to Germany,

German customs typically checks 30% of the incoming luggage. Good luck.