How to install ShadPS4
This experimental emulators allow you to play some titles.
Open EmuDeck and go to Manage Emulators and select ShadPS4
Click on Install
Go back to Manage Emulators, enter ESDE
Click on Reset Configuration so the new system is installed
Go back to Manage Emulators, enter SteamRomManager (SRM)
Click on Reset Configuration so the new parser is installed
Read the wiki to know how to install and play your games:
Linux / SteamOS Wiki
Windows Wiki