WWII was absolutely not inevitable, you're acting like every war turns into a world war. Instead of WWII you could have just as easily had a series of smaller conflicts like the Interwar period wars (which in our time had some Balkan shenanigans esp between Greece and Turkey, a free for all in Eastern Europe with Poland and USSR invading everyone around them, Spanish Civil War, etc).

Our timeline's WW2 was predicated on Germany being led by a very charismatic part madman part gambler with a very strong ideological bent, unlike for instance the more pragmatic government of Stalin which while was brutal, was ruthlessly pragmatic and threw away every bit of socialist/communist ideology whenever it suited him (no world revolution, extra nationalism, reestablishing religion, ranks in the army, having very ruthless alliances instead of more ideologically attuned ones, etc).

Hitler would have gone much farther if he didn't purge his Jews, he would have gotten the A-bomb first or maybe at least prevented US from getting one so soon. And so much of Eastern Europe was ready to fight Stalin with him until one by one most realized Hitler was even worse, see Ukraine especially. Nazi genocidal ideology really self-sabotaged their war effort to the point where almost any other type of a leader or ideology would have been more flexible and made strategic&pragmatic alliances.

But overall nothing about WWII was inevitable, you just subscribe to that same lazy historical determinism hypothesis born out of lazy school textbooks that try to make things feel obvious by framing everything very neatly and making it all feel almost self-congratulatory, letting you pay yourself on the back by making you feel like you "totally got how all these forces made it all inevitable".

Realistically US did not have to get involved and a wiser leader would have steered Germany away from a conflict with Russia. This isn't even some crazy alt history reach, it's literally in our own original history. Bismarck always try to emphasize how important it was for Germany to have Russia on its side or at least neutral. One of his chief foreign policy objectives was to keep Russia close to Germany and away from the perfidious Anglo-French pact that kept destabilizing Continental Euro affairs because the English always played the same game, they would switch sides during Euro wars to keep any one side from dominating (see Seven Years War for instance or their constant flip flopping on allying or fighting against Russia in the 19th century).

In a timeline with a more capable German leader both WWI and WWII would have began (if they even did, WWI probably would have but 2 possibly not) with Germany and Russia on the same side, which would make it very difficult to imagine how Germany could lose, fighting only on one main front in the Continent against France. USSR would supply Germany with raw material too, via land, impossible to blockade with Anglo-American + French superior navies. In fact, with a German Russian alliance there would be no need for either powers to even care about their navy that much, the two would be able to supply each other and work in perfect synergy, Germany interwar in our time provided a lot of high tech stuff such as engines, lathes, electrical components, special alloys, etc to USSR in return for raw materials, fuel, or even space to test their weapons.

Germany could have another war with France but it would be more similar to Franco-Prussian war than WW2. Poland would probably remain as a buffer state between Germany and USSR, if both sides were wise. Or not, just divided bc of the land that Germany coveted, but again, a non Nazi German leader might just know the value of keeping a friendly USSR (at least temporarily) while finishing off France and maybe even UK. And not declaring war on US without serious provocation when US was quite reluctant to directly involve in a European war, especially after already having hands full with Japan.