So a quick Wikipedia search reveals the following:
In Germany, the game was placed on the Index List of the Federal Department for Media Harmful to Young Persons.
[url=https://en.wikipedia.org/wiki/Soldier_of_Fortune_(video_game)#Violence_controversy]https://en.wikipedia.org/wiki/Soldier_of_Fortune_(video_game)#Violence_controversy[/url]
Soldier of Fortune: Payback was banned in Germany, due to its high amount of violence.
[url=https://en.wikipedia.org/wiki/Soldier_of_Fortune:_Payback#Bans]https://en.wikipedia.org/wiki/Soldier_of_Fortune:_Payback#Bans[/url]
So in the case of the first game, it appears like it could technically be sold in Germany on GOG, if they could ensure no minor would be able to purchase or play it. That could be difficult (or even impossible) to enforce though. The third game appears to be banned outright.
Unfortunately, in order to comply with German law, it does not appear there is any way GOG can provide you with a copy of those games.