It has always seemed to be quite likely a German populist-nationalist party emerged in the early 20th Century, but that the specific ideology of the Nazis seemed very unusual and a bit random. Firstly, their racial ideology of who was where in the hierarchy (Japanese better than Russians, Hungarians better than Poles) didn't make much sense. Secondly, their anti-Christianity views are unusual for fascists. Thirdly, the sheer extremism of things like Generalplan Ost show they were even more untethered from reality than most on the Far Right.
So what if, for whatever reason, the Nazis aren't setup as party in the 1920s. Instead, the vacuum is filled by an alternative populist-nationalist party that appeals to many of the same things Hitler did (anti-establishment mentality, German greatness, retribution of Versailles etc) but this party is a more convention authoritarian right-wing, and also has a much bigger degree of practicality about them. What if they still focus on expansion to the East, into Czechoslovakia, Poland, Ukraine and pushing back the Russian border but focus more on integrating their newly conquered populations into being Germans rather than killing them all. They could argue they were Slavicised Goths, Vandals and Varangians.
How successful do you think such a German government would have been?