By 2011, the PlayStation 2 was a dying console. Major developers had moved on to the PS3/360 generation. The PS2 simply lacked the to handle MVC3’s detailed 3D character models, particle effects, and complex 3v3 tag mechanics without catastrophic slowdown.

Consequently, there is no official PS2 ROM for this specific title. If you are looking for a Marvel vs. Capcom

Even on high-end PCs, UMVC3 on RPCS3 has minor frame dips. The native PC version is superior.