Let’s separate fact from YouTube clickbait. As of this (update), there is no fully playable version of GTA San Andreas featuring missions, save files, and full audio on the PSP.
: Rockstar released Grand Theft Auto: Liberty City Stories and Grand Theft Auto: Vice City Stories specifically for the PSP. Gta Sa For Psp UPD
There is no official "full paper" or official release of for the PlayStation Portable (PSP) . The game was never natively ported to that console by Rockstar Games. Let’s separate fact from YouTube clickbait