It sounds like you’re looking for the of Street Fighter X Tekken — but just to clarify, Street Fighter X Tekken was never officially released for the PSP .
was officially released for PS Vita and PS3, not the PSP, so the file you are likely installing is a "homebrew port" or a similar crossover fighting game designed for PSP. Here is the straightforward guide to getting it running. 1. Requirements A PSP console with CFW (like PRO-C2 or ARK-4) installed Street Fighter X Tekken PSP .iso or .cso file. USB Cable: To connect your PSP to your PC. 2. Installation Steps (Physical PSP) your PSP to your computer via USB mode Instructables street fighter x tekken psp iso install