This is a mod of Roads to Victory . While the missions are different from the console MW2 campaign, the modders have designed levels that feel similar to MW2 missions, and the weapons/characters are swapped to match the Modern Warfare theme.
Because the game does not exist for the PSP hardware, any website offering a direct "Modern Warfare 2 PPSSPP ISO" is typically providing a fan-made mod of an existing game or, in many cases, unsafe software. The Reality of "Modern Warfare 2" on PPSSPP Official Releases: This is a mod of Roads to Victory
This fan project is often titled or “MW2 Remastered for PSP” . It features: in many cases