How about Poles lose Battle of Warsaw, Trotsky successful and triumphant is better choice than Stalin (or he purges Stalin being stronger). Communists are stronger in Germany and Hitler gets killed in clashes with Commies. Some German Mussolini acends in Germany. Hungary remains commie, other regional countries are either unstable on the verge of commie takeover. Spain falls to commis. France has problem with commie terrorism, much like OTL West Germany or Italy.
A German Mussolini is quite possible if Hitler is thrown under the bus early enough, but even more likely is a nationalist-conservative regime change spearheaded by the Heer that restores a semi-authoritarian Honenzollern monarchy. Panicked by the Communist expansion in Eastern Europe, the Entente lifts many (and in due time, all) military limitations and reparations on Germany and allows the Anschluss to happen. Poland is overrun as per PoD (Germany in all likelihood is able to re-establish the 1807 or even the 1914 border during its military collapse), Hungary stays Communist if the Soviet win early enough and the Baltic states are encircled and overrun. Dunno if it is feasible for post-WWI Romania to fall to the Reds if the Communist regime is stabilized in Hungary. It is too late for the Soviets to help the Reds win the Finnish Civil War, however.
The USSR would surely sponsor Communist agitation in Western and Central Europe, and anti-colonial unrest in India and Southeast Asia, in all likelihood to no avail, but pissing off the Western powers to no end. They would also throw a lot of support to the CCP in the Chinese Civil War. They may aslo try to destabilize Persia.
I highly doubt Spain would ever manage to fall to the Communists, however. The European powers would throw a lot of support to any anti-Communist proxy in a SCW equivalent and basically out-supply any aid the Soviets may send to Spanish Reds (if necessary, the European powers may easily blockade Spain and stop any such aid). ITTL a united anti-Communist front of Germany, Italy, France, and Britain would take form well before the SCW in all likelihood. Soviet expansion in Eastern Europe and aggressive attitude in Asia would quite suffice to prompt its formation.