If the patch is an IPS/PPF/xdelta against an ISO
: Launch the PPSSPP app and navigate to the folder where you saved the patched ISO.
Drag and drop the contents of the translation pack into the emulator's PSP folder, replacing any existing files if prompted. :
Yes – but some item names will remain Japanese in the save file. It’s recommended to start a fresh game for full English experience.
This is the most common way to play with translations today.