Before anyone asks, yes I got this idea from Hearts of Iron, HOWEVER I still think that this reasoning can work, so here the idea: Let's say that Hungary does accept it's northern provinces from puppet slovakia and Northern Transylvania under the Diktat, and during the invasion of Yugoslavia Hungary does gives supply for the axis but doesn't directly attack Yugoslavia, and it later is "given" some minor parts of Vojvodina. During the war Hungary continues it's neutrality-pro axis and send some form of division blue like the spanish to take part on barbarossa, but the germans still get's crushed from both sides and Germany is divided, while Hungary cut off all ties with the axis on the later months of war and takes over many german technical expertise by holding off fleeing war criminals.
In OTL, after the war ended the regime of Franco was declared unlawfull by the UN and it had it's ties with the west cutoff, until he allowed the US to use bases in his country in the mid cold war:
About the above scenario with Hungary, I have two questions:
1- Is this Hungarian expansion possible, or the soviets and the allies would declare war on Hungary on the middle of the war and later defeat them as OTL?
2- If this expansion is possible, would Hungary be a post war pariah state like Francoist Spain, or would it be more like Argentina who did take axis war criminals but didn't suffered such treatment? What if the Hungarian government, be under Horthy or a fascist monarchy (NOT the Habsburgs, for the love of sauerkraut) declares to be pro Western allies immediately after the war and call new elections?