> Here in Germany "Mein Kampf" is illegal to sell.
It's not that simple. (in short, unedited and uncommented reprints are problematic (but not directly established as "illegal to sell" currently I'd say), pre-1945 printings are fine, commented editions exist and are fine)
Until 2016 all new printings were stopped on copyright grounds by the state of Bavaria. Hitlers registered address at time of death was in Munich, so the state of Bavaria acquired his assets and used that to stop printings (internationally not often successful, and with the exceptions of US and GB, where the rights had been sold to Random House by Hitlers publisher), but 2016 (70 years after death of the author) the copyright expired. Copyright was fairly straight-forward legally, commented editions now are too.
It's not that simple. (in short, unedited and uncommented reprints are problematic (but not directly established as "illegal to sell" currently I'd say), pre-1945 printings are fine, commented editions exist and are fine)