Closest you will get to "MKX on PSP". Cons: Glitchy, frame drops, requires custom firmware (CFW) on a real PSP, and is hard to find safe download links.
It is a mod of Mortal Kombat: Unchained where creators replaced character models, stages, and UI to mimic MKX. It includes: mortal kombat x psp iso highly compressed better new
The Krypt's Last Compression