A lot depends on what kind of Central Powers victory are we talking about.
If it's a four year long, drawn-out conflict resulting in Russia withdrawing due to the October Revolution, the US staying neutral and France falling after the German 1918 spring offensive, like most CP victory scenarios present, then Germany, even a victorious one, is still going to be in the shitter, there is going to be revolutionary activity inspired by the October Revolution, an overall disappointment with the war and the destruction it caused, and quenched nationalism both in Germany and elsewhere as the country returns to normal, so if you fondle with the parameters a bit and give Hitler a little bit of luck, then I think you could realistically see Hitler enter politics even in a CP victory scenario.
Hitler could still be appointed into the Aufklärungskommando after the war (it's not like he had any other career prospects than the army) and thus get in contact with the DAP to take control of it and transform it into the NSDAP, nothing in this sequence of events is removed by Germany winning WW1.
I would imagine, though, that the NSDAP in the German Empire would be significantly different. For one, it would probably lean more in favor of the German monarchy, maybe be more moderate in some aspects, and instead of calling for revenge and destruction of Bolshevism, it would campaign for Germany maintaining an interventionist attitude in Europe, "keeping the defeated Entente down", stamping out the Soviet Union as a threat to Germanic supremacy over Europe, and obviously integrate the German-speaking territories of Austria-Hungary into the Empire.
As such, these "alt-Nazis" would probably be a lot more integrated into the German political sphere, they might not even be regarded as an anti-systemic party, just loud, extreme and slightly obnoxious anti-semitic nationalists, a manifestation of Volkisch ideology. Obviously they'd still be Nazis, but viewed by the public differently and espousing a different ideology.