These settings can modified in the Pad settings menu. However, since console games are usually not designed with a mouse-controlled camera in mind, game developers usually utilize custom deadzones and use custom acceleration multipliers for the analog stick. Or alternatively, you can also map the mouse to any other button(s). Click on one of the Right Analog’s directional buttons, then click-and-hold, while moving the mouse in the appropriate direction.Ensure the Mouse Handler in the I/O Tab of the Settings menu is set to Null.If you wish to map the mouse movement to buttons in the keyboard pad handler,

This is only present in a handful of titles on the PlayStation 3. Using mouse in games with native support for Kb+M Note: For this to work, the game must natively support the Keyboard+Mouse set-up.

The first is where games have native support for Keyboard+Mouse and the second is manually mapping your mouse to controller buttons in the Keypad handler. There are currently two methods to use the mouse movement with games on RPCS3.

How to use keyboard on pcsx2 emulator