Theoretically, if you could replace the map files, mission scripts, and textures from Vice City Stories with those from San Andreas , you might get something to boot.
Apps like and RetroArch turned the PSP into a client device. If you had a PC powerful enough to run San Andreas , you could stream the video feed to your PSP over Wi-Fi. It wasn't a "port," but it was the first time you could legitimately drive down Grove Street using Sony’s handheld. It was a technical marvel, bringing a preview of the cloud gaming future to a device released in 2004. gta san andreas psp homebrew
These early attempts paved the way for modern handheld ports we see today. If you'd like to dive deeper, I can find: Real technical specs of the PSP vs. PS2 Theoretically, if you could replace the map files,