PPSSPP is an emulator for PlayStation Portable (PSP) games. But God of War Ragnarok is a PlayStation 4 and PlayStation 5 game, not a PSP title. So there's a discrepancy here. The user might be looking for an emulator version of a game that isn't compatible with the emulator they mentioned.
If you own a PlayStation, you can stream the game directly to your phone. God Of War Ragnarok Ppsspp Highly Compressed BEST - Google
Legitimate PSP games can be compressed from ~1.5 GB down to 300-500 MB using (not fake ZIP/RAR files). This reduces load times slightly but works fine on PPSSPP. PPSSPP is an emulator for PlayStation Portable (PSP) games