I think everyone here is forgetting that the wars in Algeria and Vietnam (the French and American ones) were fought by democracies, and also forget the kind of war Fascist Italy fought against both the Libyan rebels and Ethiopians themselves. In the former three wars the citizens of France and the US had enough freedom of expression to signal their opposition to the wars their nation was involved in, and frequently took that opportunity, sometimes in increasingly illegal ways (ex: American college students burning their draft cards and firebombing ROTC centers). There's zero way Mussolini would tolerate the same level of dissent. Secondly it's worth remembering Mussolini had his own system of
concentration camps and drenched Ethiopia with chemical weapons. Despite the brutality visited in Algeria and Vietnam, neither the French or US were willing to go that far to win their respective wars.
This is also keeping in mind we're not even mentioning what Mussolini was willing to do during WWII, both before and after 1943. We have to seriously ask if there would be an Ethiopian population that survives a serious war of resistance against a longer living Fascist Italy.
Don't forget South and Central America either. There were a number of figures in both regions broadly sympathetic to or willing to work with fascists both before and after WWII, some of whom openly admired Mussolini (like Juan Peron).
Without Nazi Germany invading the USSR the Soviets are going to be in a stronger position than OTL by virtue of not having 27+ million of its population killed. Depending on how the inter-war period goes we could actually see a
Red Alert type scenario where its the USSR who serves as the main threat to European security through the 30's and 40's.