I did some reading on Heinrich Bruning's plan to restore the German Monarchy during the very unstable months of 1932. In his plan, he proposed that one of Wilhelm II's sons would assume the throne as a constitutional monarch, on the British model whilst Hindenburg would serve as a regent until his own death. This however, was opposed by the increasingly senile Paul von Hindenburg due to his reactionary affection for Wilhelm. When Bruning informed him that both the SPD and the international community would not tolerate this, he threw him out of his office.
I have identified several issues with it's restoration.
1. The Catholic community in Germany would not be pleased with the return of the Hohenzollern dynasty, due to its association with repression. Wilhelm returning is out of the question.
2. While Bruning supposedly claimed he had support from the SPD, I feel some of that may have been fabricated.
3. Wilhelm's eldest son was involved with the Battle of Verdun and wasn't look upon positively.
3. Violence could intensify between NSDAP and the KPD.
4. The French will no doubt be indignant that the Hohenzollern monarchy is back on throne.
This in effect, either leaves the Bavarian branch of the monarchy or Louis Ferdinand, Prince of Prussia.
Is it possible?