The Nazis weren't internationalist socialist.
They pretended to be, adopted popular socialist policies
So they adopted socialists policies . . .
...and claimed to represent the people against the establishment.
The treatment of workers and unions under National Socialism would be familiar to workers and Unions in the Soviet Union at the time.
As soon as they got into power they dropped the pretence.
After the National Socialists rose to power they began collaborating with the Communists in the Soviet Union. They signed a non-aggression treaty, conspired in the invasion of Poland and the splitting of its territory, exchanged political prisoners of interest to each other. When the National Socialists invaded France, the French Communist party applauded their actions and worked with them.
After taking power the National Socialists, like the Communists, began killing. The Communists mainly killed by class, the National Socialists by race. Marx and Engels called for both the killing by class and by race.
Maybe you should watch The Soviet Story, there seem to be some gaps in your knowledge. (It would be better to watch a copy from the library so you can to get the subtitles.)
In your thinking "socialism" seems to be either a substitute for, or conflated with, "good". It still baffles me how you regularly defend the evil regime in North Korea.
Revealed: the gas chamber horror of North Korea's gulag
Even the Guardian gets it. If you can defend North Korea as "not so bad," (as you did some months ago) is there anything Stalin did that you personally couldn't defend? I'm not sure how there could be other than the fact the DPRK exists and Stalin's USSR doesn't.