Ukraine is more of a vassal than one of the bigger imperialists, it's used similarly to how Israel is by the US Empire. It's itself being harvested for rare Earth minerals and shackled with tons of debt while at the same time being used to attack enemies of the west. Hungary is both a NATO and EU member state, it's firmly on the side of the imperialist system.

Imperialism essentially is monopoly capitalism at its most developed stage, turned international. In the modern day, the US Empire is at the helm of this, with the EU and other NATO countries being used to protect this system of international extraction. By being in NATO, Hungary plays a part in defending this system, and by being in the EU, it benefits from imperialist spoils.