And speaking about Munich-even "notzi" Germany would go for Austria first and then for Sudetenland, because these were easier goals than Corridor and Germany could use ethnic argument (raised by Allies themselves after ww1) to justify these annexations.
II don't think that is certain at all. The Austrian naziparty's popularity rose when the popularity of the nazi's in Germany rose. If Hitler is dead in WW1 or at the putsch in 1923, it's a question if the nazi's will rise to power in Germany. This will also effect the naziparty in Austria and they may not rise to power.
The Austrians may still want to unify with Germany, but in OTL Hitler send an ultimatum. A nozi-leadership maybe doesn't do it, and instead of the Wehrmacht marching into Austria, Austria may be unified with Germany (more) peacefully and at a later date. This will impact the view in France and the UK.
In OTL the timeline is as follows:
- 1932 Hitler rises to power and establishes a dictatorship
- 1935 Saarland votes to be part of Germany
- 1936 remilitarization of Rhineland
- march 1938 Anchluss (9 march a referendum is announced for the 13th, 11 march Hitler issues an ultimatum, 12 march Wehrmacht marches into Austria)
- september 1938 Munich treaty, Germany annexes Sudetenland
- march 1939 Germany annexes the rest of Czechoslovakia
- august 1939 Molotov-Ribbentrop pact
- september 1939 invasion of Poland
- april 1940 invasino of Denmark and Norway
- june 1940 fall of France
- may 1941 Barbarossa
If Hitler is dead before 1930, things will change. The only thing on this list that I'm pretty will be the same is the Saarland vote. Everything else (most notably Hitler being the Führer in 1932) is subject to change. Hitler/the nazi's may not issue the ultimatum to Austria in 1938, meaning there is a referendum and Austria may vote voluntarily to join Germany. Or with no Austrian nazi's in power, there is never an organized movement in Austria to join Germany.
Even if they will annex Sudetenland, the nozi's may not annex Czechoslovakia.
Even if they invade Poland with the USSR, they may decide to be content with Danzig and East Prussia and leave a rump Poland.
Even if they don't, the peaceful anschluss and not having annexed the rest of Czechoslovakia may mean France and the UK don't see as much reason as OTL too sign a defenceagreement with Poland.
Will the nozi's invade Denmark and Norway as in OTL?
Even if France falls, the nozi's may count their blessings afterwards and sign a peace and be just content with Alsace-Lorraine, Eupen-Malmedy and maybe some parts of the Netherlands.
Even if they continue to war, the nozi's do not have the same quest for Lebensraum in the east and probably won't attack the USSR.
Even if everything happens, it doesn't have to happen in the same timeframe. Which in itself may lead to major changes in the course of the war.
There's also the rebuilding of the military in Germany. Nozi's may do it slower than the nazi's, which will effect the size of their army in 1939.
So there's lots of things that can change if Hitler is dead before 1930 and the nazi's never rise. While you're making it sound like "whoever rules Germany, they will make the exact same decisions as Hitler did." Especially the ultimatum to Austria and the annexation of the rest of Czechoslovakia. If these don't happen, it's very likely the UK and France won't be as worried/feel as threatened as they did OTL. And if then the next move of the nozi's is towards Danzig and the Polish corridor, that may the Munich treaty of TTL.
The nozi's maybe content at that point and WW2 is averted. Or maybe they'll lay their eyes on Schleswig-Holstein, Eupen/Malmedy and Alsace-Lorraine next and you get a different WW2.