Bobbykaze | Super Monkey Ball Adventure (PSP) - Unlocking Future AiAi (Save File in Description) @bobbykaze | Uploaded October 2021 | Updated October 2024, 15 minutes ago.
It seems that there is a lot of confusion on how to unlock Future AiAi on psp so I wanted to make this video. Basically you need to 100% the game (just once) but before the final mission talk to the Mysterious Traveler in the 5 locations shown in the video then go do the final mission with autosave enabled and it should unlock Future AiAi.

Here is a download link for a save which has Future AiAi unlocked on the USA version of the game - mediafire.com/file/7p8ml0if6wcztjo/Future_AiAi_Save_%2528USA%2529.rar/file