How to add PS3 games to Steamdeck RPCS3 emudeck, PKG/RAP info and controller Help
Sorry for the quality, but in this video is a step by step instructions and info in how to install PS3 games on your Steamdeck. links below
RPCS3 compatibility list:
https://rpcs3.net/compatibility
note some PKG files need a RAP file. add both through the File drop down in RPCS3. ISO folders can just be dragged into the empty list. I do recommend a PS3 or PS4 controller and a Dock with a mouse makes it easier to navigate.
Comment with any questions you have