The only requirement to have avoided the Second World War would've been to avoid the Great Depression because it was that alone that allowed the Nazis to rise from being an obscure party with 12 seats in the Reichstag in 1928 to 230 seats in 1932.
It's worth bearing in mind that the Nazis were not the only anti-democratic party in the Reichstag and being anti-Semitic and anti-Versailles Treaty were not exclusive to the Nazis. The Nazis only got into power because of their promise to create jobs, restore national pride and rid Germany of its enemies. For people who had lost their livelihood in the Depression these things were music to their ears.
No Great Depression = no Nazis in power = no Second World War.
It's worth bearing in mind that the Nazis were not the only anti-democratic party in the Reichstag and being anti-Semitic and anti-Versailles Treaty were not exclusive to the Nazis. The Nazis only got into power because of their promise to create jobs, restore national pride and rid Germany of its enemies. For people who had lost their livelihood in the Depression these things were music to their ears.
No Great Depression = no Nazis in power = no Second World War.