It is not possible to write a guide or essay on the "best" way to download Mario Kart 8 Deluxe for the PSP because the game does not exist on that platform.
. The PSP was released in 2004 and lacks the hardware architecture to run a modern Nintendo Switch title from 2017.
PC Streaming (Remote Play): Some users have successfully used tools like PSPdisp to mirror a PC screen to their PSP, effectively "playing" the Wii U version of Mario Kart 8 by using the handheld as a wireless controller and monitor. Best Native PSP Racing Alternatives mario kart 8 deluxe psp download best
Mario Kart 64 (N64): Playable but often requires disabling audio to reach "full speed".
: Features deep kart and track customization similar to the "Deluxe" experience. Crash Tag Team Racing It is not possible to write a guide
While there are PSP emulators for PC (like PPSSPP), there is no functional PSP emulator that runs on a PSP (that doesn’t make sense). And there is no known emulator that can make a Switch game run on original PSP hardware. The architecture is completely different.
Best Mario Kart Games for PSP
The Setup: Run the Wii U version of Mario Kart 8 on a PC emulator and use PSPdisp to mirror the screen and use the PSP as a wireless controller.