Marshall Zhukov had already slapped around that million man Kwantung Army at Nomonhan in August of 1939. Japan wanted no more of the Soviets ever after. As for the Japanese marching on Moscow, an over 3,000 mile trek, it could never happen successfully. The Japanese Army in Southeast Asia virtually starved to death by the end of the war, how would they have supplied their forces with enough resources to go on fighting. The infrastructure of Siberia was not up to snuff to allow it, and Japan did not have the industrial capacity at the time to build one in a timely fashion.
Interesting story in Anthony Beevor’s “World War II”. An ethnic Korean soldier in the Chinese Army or local Manchurian militia is captured by the Japanese in their conquest of Manchuria in 1931. The guy is then dragooned into the local puppet government’s, Manchukuo, forces and then captured by the Soviets in a border skirmish. The Soviets let him out of the POW camp when he enlists in the Red Army. He is captured by the Germans in the winter of 41-42 outside of Moscow. The Germans draft him into their own forces, and the Korean guy ends up on the beaches of Normandy where he ends the war as a prisoner of the US Army.