The files you see online are usually "Mods" or "Skins" for an older PSP game called Mortal Kombat Unchained Official Alternatives for Android

: Many websites offering "highly compressed" versions of modern console games for emulators provide files that may contain malware or broken data. Better Alternatives for Android

Search Google for "Mortal Kombat X PPSSPP ISO Mod" or "Mortal Kombat Unchained MKX Mod". You will typically need three files: the ISO (Game File) Texture Pack Extraction Process (Using ZArchiver): Extract the game zip and move the file to a folder named on your device. Extract the Texture Pack and move the resulting folder into PSP/TEXTURES Save Data: Extract the Save Data and move it into PSP/SAVEDATA Run the Game: Open the PPSSPP app.

Would you like a guide on setting up on PPSSPP for Android instead? That’s your safest and most authentic option.