If we assume that everything goes as OTL sans US aid, it's probably not happening. The Soviets can eventually push the Germans out of Western Russia but the offensive will stall somewhere around Warsaw at best. This is particularly true if they can't starve the populace to free up manpower for tanks AND logistics.
If we're assuming stuff like "Stalin focuses the Moscow counteroffensive against AGC and breaks it to bits" or the many other ways 1941 could have gone wrong for Germany, well, they can beat Germany and Italy between 1943-1944, but they still have to deal with Japan, and while they'll mop up Manchuria, I don't think the Brits or the Soviets can successfully invade and occupy the Japanese Home Islands (AND force a surrender, let alone Unconditional Surrender) before August 14, 1945, unless they somehow get the bomb, and their strategic bombing and submarine capability is not going to cut Japan off from resources or destroy her homefront to the same extent that the USA could have. And the RN is probably a tie to slightly better than the IJN, and they're going to be fighting on 2 fronts until 1943 at the earliest. Certainly they are not going to outproduce the IJN to the enormous extent the USN did.
If no M-R pact then Germany crashes sometime in 1940 and Japan doesn't even get in the war (this is assuming no embargo btw, so no attack on the DEI which means the Brits might not even go to war with Japan).
If Fall Gelb fails pretty similar situation.
Japan will go down eventually in this scenario, but almost certainly not by August 14.
Don't think it can be done in terms of beating ALL of them.