"The PS4 scene is going at the speed of light, and it’s been difficult to keep up.
After the doors being opened for a flood of PS4 piracy, the scene now gets PS2 isos. Yesterday, developer CFWProphet released a tool named free-ps2-pub-gen, which allows PS4 owners to embed a PS2-PS4 (as in “PS2 game released for PS4) iso within a PS4 package for use with PS4Hen. The tool implements Flatz’s recent writeup on how to emulate PS2 games on the PS4, and wraps it all up in a GUI.
Multiple people have been reporting that the initial release of the tool has issues, but others have been confirming it works. CfwProphet stated he has a fix and will release an update.
Scene veteran CelesteBlue has posted a video of a PS2 game in action:
A working package file has been floating around, with people suggesting that replacing that specific game iso with any other ps2-ps4 iso would most likely work. The readme of free-ps2-pub-gen implies things should work directly with the tool, though."