[ Even though the Nazis were national socialists, they still had ambitions to rule globally. So eventually, they were headed in the same direction as their international socialist brethren. ]
NAZIs still believed in invading and taking over countries via war like the classical European model of conquest that Napoleon used.
The Soviets believed in using internal subversion first to do a lions share of the work before they rolled the tank into the country and would not “officially” take over a country but instead place “Party members” in power over a country to turn into into a satellite or puppet state. This made the invasion seem less like an invasion.
So in this way NAZIs were more “honest and upfront” about their invasions than the Soviets were.
It is the difference between being chased down, killed and eaten by a Tiger vs. catching a parasitic disease, getting weakened, then dying and ate by scavengers.
Both the nazi way and the soviet way were ugly, but both ways tried to end up the same place: socialist dominance over the globe.
The most significant difference was in the personalities involved. Both movements basically accepted Lamarckian premises that people could be reengineered by control of their social environment--the common fallacy of all Leftwing movements.
See Lies of Socialism.