You have to prevent the Red Army purge at the very minimum, and get rid of Stalin. This before 1936.
Then the Nazis could be in for a nasty surprise. Like discovering the Soviets were expecting them with entire echelons of reserve armies and air fleets arrayed in depth behind a n elaborate wall of maskirovka, fake airfields, dummy fortifications and tanks, etc. Their attack, while mauling entire armies and reaching the Dvina-Dnepr line, collapses by winter. Soviet revenge is swift, massive and decisive. Despite anything that Nazi Germany can put into the field - the best armies, the best troops, the best commanders, the latest weapons - by summer 1942 the situation is so dire that Libya has to be evacuated (the Royal Navy fails in the attempt of interfering). The Weastern Allies ditch any attack on North Africa, not to mention Italy and the Mediterranean, and concentrate all forces in England for Roundup. On November 11th, 1942, they struck into Brittany with a British paratrooper division and seven Anglo-American abnd Canadian divisions, quickly taking Brest to secure a port. In the East things go down so quickly and clearly for the Nazis that Italy, having sent no reinforcements to the East in 1942 despite Germany's desperate urging, by Christmas overthrows Mussolini and signs a separate armistice with both the Western Allies and the Soviets (a sort of white peace "only" entailing the loss of colonies, Zara and Fiume, differently than in OTL), without having been invaded or even heavily bombed. The few German units still in Italy are overcome and interned; the Luftwaffe's terror bombing of Italian cities only causes a complete "renversement des alliances", very much Savoy-style. In the end it's Italian troops that occupy most of Austria (save Vienna and Graz) and southern Bavaria with Munich, finding surisingly little resistance and less hostility than expected. The Western Allies charge through a France in turmoil between Gaullists, Communists and die-hard Vichy Fascists. By the first days of March 1943 the Soviets are on the Oder, the Anglo-Americans on the Rhine and Italian troops have penetrated deep into Austria. General von tresckow manages to kill Hitler with a bomb, after which everything just collapses quickly. the Western Front is willingly opened by Wehrmacht commander whereas in the East ferocious fighting goes on up to the formal surrender of Germany on all fronts signed on April 20th, 1943 in Flensburg.
By summer the Soviets attack the Japanese in Manchuria, crushing them. In February a coup removes Tojo and Japan surrenders - avoiding direct military occupation, save for Okinawa, and losing all colonies and possessions.