This post will reveal my lack of knowledge on the Eastern Front, but would there have been any way for Hitler to have gotten to the Soviet Union without directly attacking Poland?
If someone with a time machine goes back to 1935 and decides to help Germany and Japan, would there be a way?
Have Hitler work on his “image problem” in the West, have him spend all of his energy painting Communists and the ultimate evil. The Nazis can wait to do their genocide later.
Conduct secret pacts with France and the UK in which Germany promises to respect Poland territorial integrity. Renegotiate the Versailles treaty rather than unilaterally break it. Don’t remilitarize the Rhineland.
Transfer German manufacturing and military technologies and concepts to Japan. Train Japanese generals on fighting modern armies.
Keep Japan out of China by all costs, promising Siberia, or large chunks of Eastern Siberia to them.
Secretly promise Poland large chunks of land to their east if they cooperate with you. Help train and modernize their armies with German weapons, but don’t increase their manufacturing capabilities.
Secretly promise people in Ukraine independence if they support you once the fight begins. Same for Belarusians.
Secretly promise Finland, Lithuania, Latvia and Latvia large chunks of land to their east if they cooperate with you. Help train and modernize their armies with German weapons, and help them increase their manufacturing capabilities.
Promise parts of Soviet territory to Hungary and Romania if they cooperate with you. Help train and modernize their armies with German weapons, and help them increase their manufacturing capabilities.
Promise Mussolini German cooperation with North Africa, Yugosolavia and all if they first help fight the USSR. Help train their armies and increase their manufacturing capabilities. Once they are committed in the fight against the Soviets, help stage a coup and put the generals in charge. Mussolini is too much of a wild canon so he’s got to go.
Manufacture more light tanks for the initial attack. Use German tank units combined with Polish cannon fodder to attack head on while using German troops and tanks for the pincer movements.
Secretly pre-stage German equipment in Finland, Poland and other countries. Then do the massive surprise attack, as well as having Japan simultaneously attack in Siberia.
With Leningrad so close to the Finish border, you should be able to capture it quickly.
Learn the damn lessons about logistics and specifically figure out how to use the Soviet rail system to get troops, tanks and supplies close to Moscow as soon as possible. Figure out how to solve the wide track vs. narrow track issue and all the other problems which plagued the Nazis.
Capture Moscow and strip it of all the manufacturing factories and equipment, keep the lion’s share and distribute some to key allies.
Then start to wipe out the civilians.