is not a PSP game. It was developed by Level-5 exclusively for the . There is no official "PSP ROM" for this title because the game was never released for that platform.
To summarize:
The legitimate PSP titles are:
"The ROM isn't a game," Tsurugi said, stepping forward with a smirk. "It’s a bridge. You wanted to play the ultimate version? Then show us your Keshin." inazuma eleven go strikers 2013 psp rom free