A few points on France and Italy:
I notice on these boards a general assumption of France and Italy vs. Germany as a more "logical result". Someone said it was "more in Italy's interest", which as it turns out in hindsight is true, but that's really more of a hindsight kind of observation.
While a few Italians forsaw the serious mistake of the Italo-German Axis such as Balbo, there's a real reason most saw throwing their lot in with Germany more in their "best interest".
To understand Italo-German-French relations we have to understand Italy's main strategic concerns. They're a peninsula nation with nearly every point in the nation within an hour's drive to water. The population far exceeded the nation's agricultural, mineral and industrial capabilities, making it overwhelmingly a net-import nation, and one almost wholly dependent on sea trade.
This made them very vulnerable to naval threats. This made the Adriatic, Suez, Dardonelles, and Gibralter of extreme strategic/logistic importance. Corfu and the Dodecanese were not just force projection points, but vital points for control of the Adriatic sealanes. As Italian-Albanian ties grew stronger and Italian-Yugoslav relations grew worse, there was a real fear that a hostile naval nation operating from Dodecanese ports could devastate the Adriatic coast and sealanes. The growing Franco-Yugoslav partnership of the 20s made the fears of French ships on the Adriatic coast very imminent. Corsica offered an equivalent threat to the western shore. The shore-side cities were vulnerable to sea bombardment. Trade in general was vulnerable to any nation that controlled Gibralter, Suez, and the Dardonelles. Obviously this includes Britain, Greece and Turkey, but it also includes France who held control over Morroccan ports and was cosying up to Yugoslavia.
In the west, the old border and cultural issues over Savoia and Corsica were very much still real. Also worth note was that the industrial heartland of Italy was in the northwest and very vulnerable to invasion from or through France.
On the northern front there was the old emnity with Austria over Trieste and Trento, of course, and the old emnity with Germany, and fears of an Austro-German alliance were strong, including plans on dealing with Germanic invasion through neutral Switzerland.
However, the naval threat, Adriatic threat, and northwest threat were the foremost concern. Mussolini wanted the Dodecanese BAD. In the words of John Gooch (Mussolini and his Generals) Mussolini "despised" France. Even Germanophobe Balbo had his eyes cast on France as a likely adversary. Italian plans for war with Yugoslavia and War with France were the top priorities. Interestingly, plans for a two-front war vs. France AND Yugoslavia were
not made based on the "we're screwed in that case, so why bother" theory.
At the Washington Naval Conference and similar naval treaties pairity with France was the foremost concern, and the inability to fund or produce a navy equitable to the growing French one was a constant danger.
Then there's French-held Tunisia, it's proximity to Italian sea lanes, and the ever-more-repressed (in Italy's view) ethnic Italian population there.
Simply put, in the inter-war period most in Italy saw France as the most likely major-power adversary in a war. They equipped, planned, and strategized for a land and sea war against France. They also planned for war possibilities against Germany and/or Austria, but France was the likely enemy in most scenarios.
The Locarno pact was signed by Italy, but generally feared for the implications of a Franco-German detente, and Mussolini and others secretly celebrated the death of Stresseman as a hope for a freezing of Franco-German relations. The Stresa Front was in direct response to Nazi aggression and while this is indicative of the real fears of a German-Austrian front against Italy, it should be remembered that this did not indicate a lessoning of Franco-Italian rivalries.
While an ATL Franco-Italian front against Germany is a real possibility in a realpolitik way, one should keep in mind it was not a "sure thing" and OTL's Italo-German front against France was just as if not more likely, considering the very real strategic rivalry between France and Italy.
Just some things to keep in mind in any alt-post-WWI Europe TL.
Sorry for the novel here, but I've recently become quite familiar with Italian strategic and diplomatic concerns thanks to my research for Viva Balbo. If you get a chance read Mussolini and his Generals by Gooch; it's a VERY dense but very informative look at Italian inter-war strategic/diplomatic/logistical issues.
Hope this gives some insights and isn't just an eyesore.