Hyperinflation in Germany was a symptom not the direct problem. WWII was a direct result of asinine conclusion of WWI. If Bitcoin existed (and was the sole global currency) WWII would have happened exactly as it did. Remember money is merely an accounting system. Germany had plenty of real wealth. Most of WWI was fought OUTSIDE of Germany and while Germany "lost" they retained a massive industrial complex which rivaled their neighbors. Now their neighbors decided to "punish" Germany in the peace treaty with utterly asinine conditions and Germany decided ... how about we stop paying the equivelent of 30% of your GDP in war reparations. Of course once they broke that conditions (w/ no consequence) it became very easy to see how/why they broke all the other conditions (keep to prewar borders, remain demilitarized).
The short/simple version:
Making a peace treaty which "punishes" the more powerful nation who happened to lose the previous war and then not backing that up with military might is almost certainly going to lead to a second war.
None of those of course excuses the atrocities committed by Germany but in hindsight WWII was inevitable given the resolution of WWI. Bitcoin wouldn't have changed that.
its possible bitcoin could have prevented the weimar republic's hyper inflation (because they wouldn't be able to print money).
although this would have caused them to default on the reparations it would allow them to start producing goods again and would prevent or lessen the economic suffering that they had in the 30's.
this in turn might have stopped hitler from rising to power thus likely averting ww2.
The same thing could have happened without Bitcoin. Hyperinflation didn't cause Germany do break the peace treaty. The punitive peace treaty is what lead Germany to break it. Germany could have been on a gold standard (forget that they could have been using pure gold coins) a peace treaty which imposed a penalty in excess of 30% of Germany GDP was simply broken. It produced real economic and social suffering "at home". At some point people are going to say "WTF? He got factories lets just spend 30% of our GDP on making guns and bombs and stuff instead of handing it over to foreign powers". Of course Germany could have just broken the reparations portions, but treaties as simply promises. It becomes easier to break all of the promises once you start breaking some of them.
WWII was inevitable given the asinine decisions made at the close of WWI.
Lets take
a) a nation with a massive industrial complex
b) history of military aggression
c) political will to justify expansion through military force
d) a belief (dubious as it might seem) that the territory (namely Poland) was fairly conquered and then "stolen" in the post-war treaty.
Now lets add
a) punitively impossible post war terms
b) absolutely no mechanism to force compliance with said terms.
c) a group of nations that when Germany began to break terms didn't react swiftly and decisively.
Oh look, who could possible imagine that the nation would break the terms are return to expansion through military might. I mean it seems utterly implausible in hindsight right?