quoted from alek.dark-alex.org/pspwikiIt is the first cheating program on the PSP. It allows cheating in UMD Games & ISOs, as well as PSX games (through POPStation on 3.XX OE, 3.XX M33, 3.XX LE & 3.XX HX firmwares) on the PSP. It is functionally similar to legacy cheating devices such as Gameshark and Action Replay. It is also currently the only known homebrew application that allows the conversion of PSP-format PSX memory card files into the format used by popular PC PSX emulators such as ePSXe, allowing a user to migrate their savegames between their desktop PC and PSP
download the app here
download the latest database here
follow readmes, and enable the plugin in recovery mode. while ingame, hold down "select" to access the CWCheat menu.