What happens to Poland then? I'm guessing they try to pull out early and make a deal.
Even if they switch sides, they'll be made into communists like Romania was IOTL. As far as Stalin (and the West) is concerned, they just proved their hostile intention by aligning with Hitler. The WAllies are going to be more concerned with the fate of Germany (since there is the very real possibility of Soviet troops on the Rhine ITTL) instead of Poland.
On another note, won't the Soviets be facing the full force of German air power? Isn't that going to make victory alot hard?
Not once the VVS gets enough experience and equipment under their belt to wrest air superiority away like IOTL... or when the Germans run out of oil in 1941.
In addition no lend lease so the Soviets aren't getting any help.
Doesn't matter. Most of the big industrial regions that were captured IOTL are still in Soviet hands ITTL. With that, the Soviets have enough industry to not only produce an even larger quantity of guns, tanks, and artillery but also provide the logistics for their army.
In fact without what they looted from Western Europe, without the imports of material from the USSR in 1939-1941, and with their shitty financial situation the German war industry is fucked.
But the logistics could have been sufficiently alleviated (in the opening stages) with a rail line from Berlin-Poznan-Warszawa-Brest.
That does not make up for the fact that the Germans don't have the quantity of trucks they need to provide
any degree of motorization to their logistics, not even the partial motorization they had IOTL 1941.
More importantly, without a war in the west to convince Stalin to re-arm faster,
No war in the west probably means Stalin is rearming even
more frantically ITTL. After all, the whole point of the Molotov-Ribbentrop Pact was to deflect German attention westward so as to give the time to prepare. ITTL there is no Molotov-Ribbentrop Pact, no war in the west, and the Germans have just spent the fall and winter of 1939-1940 building up on the Soviet border. How do you think Stalin is going to interpret that?
you will most probably see a German defensive war,
...
What?
Which does not mean the Soviets will escape the horrific encirclement that they experienced IOTL 1941.
Yes and no. Encirclements will still happen but breaking through the heavy defenses will take the Germans longer, at a greater cost in men and material, to greater exhaustion of the German forces involved, and with more Soviet forces escaping eastward. By the time the Germans have successfully finished sealing and digesting the pockets sufficiently to move eastward again, the Soviets will have set-up a new line of defense with even more men and material behind it.
Nothing really supports that statement since historically after the German's "blitzed" through Poland and the West and the war became effectively a standstill with a massive number of German troops building up on the border, Stalin continued to dismiss the vast amounts of intelligence reports he received, as well as the warning the British gave him that the German's would attack extremely soon
Because Stalin was convinced that Hitler wouldn't attack him while the war with Britain was unfinished, while Stalin was providing Hitler with all the raw materials he wanted, and after Hitler had held up to his end of the bargain in 1939-1940. ITTL, there is no war with Britain, Germany ain't getting jack from Stalin, and Hitler has in fact betrayed the secret protocols of the MR-Pact dividing Poland between Germany and the USSR.
Barring an Allied intervention against Germany during the war (which is extremely doubtful), this can only be achieved by ASB's, unless you have an actual reason?
Sarcasm aside, you are pretending that a vastly weaker Germany will achieve
at least as much success against the USSR as IOTL, which is the minimum required for Germany to even have good odds on achieving a stalemate. There is no basis for that. Germany IOTL 1941 was at it's most powerful relative to the USSR then it ever was going to get. In 1939 and 1940, the relative strength of the two sides were much closer.
Also, some degree of Western aide for the USSR probably will be seen ITTL as the Soviets gain western sympathy for being the victim of unprovoked German aggression and the propaganda fodder subsequent German atrocities on Soviet soil will provide without any of the enmity from Soviet aggression in the 1939-1940 period to cloud the issue. That will dry up once it becomes clear that the Soviets are going to overrun Germany, but by then it will be too late.