You need a dedicated Game Boy Advance emulator designed for the PSP.
A newer, performance-focused emulator that prioritizes speed for ROM hacks and high-intensity games. Installation Steps Pokemon Sapphire For Psp
To play Pokémon Sapphire, you must first modify your PSP to run unsigned software. You need a dedicated Game Boy Advance emulator
A legal copy of the Pokémon Sapphire ROM (.gba file). such as version 6.60 or 6.61
Most emulators require a gba_bios.bin file to run games correctly. Recommended Emulators
Your PSP needs to be running custom firmware, such as version 6.60 or 6.61 , which can be installed using modern tools like ARK .
Several emulators are highly rated by the community for their performance and features: