StG. 45 Assault Rifle

Based of a what-if question that popped into my mind. What if the US never finished the atomic bomb, and ended up fighting on the Japanese Home Islands? What if the Soviets invaded Hokkaido? What sort of weapons would be used in this final battle?
Introduced in 1945 to defend the last remnants of the Third Reich, the StG. 45, the Alpenfestung. Using the 7.92x33mm Kurz round used in the StG. 44. It has managed to become a devastating weapon against the invading Allies, and has become a nuisance to occupation troops who constantly face attacks by the Werwolf units.
After the war, the StG. 45 was used by the West German border guards and the East German Volkspolizei. West Germany defaced most of the Nazi marking and sent thousands to Israel to help build its military.
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