I dont see any difference compared to other T-54/55 except added track parts on armor.
Probably these mudguards make it look unusual.
Maybe this would be useful, there are vehicles used by Hungary after WW2 listed with description:
This is a rare case where adding what is basically a reskin to a TT would be met with positivity because they are not available on the market place. It would not negatively impact their value by making them functionally free.
Having them as event vehicles only was appropriate when there was not a clearly correct TT location for them. Now that there is, they should be reintroduced as TT, given they were a major component of the Hungarian Armoured Forces. (Or intended component, in the case of the Zrinyi I not having enough domestic production of long 75mm to make it a viable option)
For the Zrinyi I, they can even drop the rockets on the TT to keep the event vehicle unique.
Side note: For those looking for good English sources of information about Hungarian WW2 vehicles, Magyar Steel by Csaba Becze is probably the best choice. It can be a little difficult to find though.