The most reliable and safest method to play PS3 games on a PS4 is through a PS Plus Premium subscription.
Use your PS4’s web browser to load the Linux payload and boot into the Gentle Linux environment. ps3 to ps4 pkg install
Place your PS3 PKG and RAP files into a folder (commonly named "DEX"). The most reliable and safest method to play
A dumped PS3 PKG file and its corresponding . Step-by-Step Installation Process ps3 to ps4 pkg install