Here is the scenario:
A different fascist regime is installed in Germany, perhaps somewhat similar to Mussolini in the sense of being more sympathetic to socialist ideas, BUT the important divergence is:
Instead of focusing on Jews and Slavs as "Untermensch" (forgive me if I mispelled, didn't bother looking it up to double check), this dicator and regime are focused on revenge against Britain, and especiallly, France.
For this reason, this regime seeks out to maintain and strengthen the ties the Weimar Republic had with the Soviet Union. This regime *is* opposed to Communism (especially revolutionary, Trotskyist Communism), largely on the grounds that it demotes nationalism and nationial community in importance, but its main concern is Communism in Germany. This regime wants to get along with Stalin, basically have a "agree to disagree" on the differences in their regimes and have a cordial relationship.
The Non-Aggression Pact (actually closer to a solid alliance) is signed earlier, as are the Trade agreements. Poland is partioned as in OTL, but in TTL, all of Germany's focus then turns to Western Europe, in terms of war and conquest, taking over France, Benelux, Scandinavia, and partitioning Britain and occupying England (Wales and Scotland being granted independence). The two powers basically divide their spheres of interest, Germany controlling Western Europe and Stalin controlling Finland, Romania, Bulgaria, and Yugoslavia. Italy is an ally of both ITL. Stalin, of course, doesn't give up on less aggressive atempts for more Soviet control and influence, but is content to avoid a war with a Western European hegemon that is friendly and allied with the Soviets, and is a helpful trading partner.
Ok, is this doable? Is there a possibility in Stalin forming an honest alliance with a non-Communist power? If so, how long before these two start to drift apart (I could imagine it would start as soon as this Germany had its revenge and a secure control in the West, myself.