PS4 modders and hackers have made a breakthrough in the last few months that allows players to side-load games. New vulnerabilities have been discovered in specific PS4 firmwares that allow for games to be run without the checks that usually make sure the game is authentic.
Thanks to the recently developed PS4HEN exploit for PS4 firmware 4.05, tools for backing up PS4 games have already been published. What’s even more interesting than that though is that a tool by cfwprophet called PS2 Pub Gen allows users to back up their PS2 games and play them on the emulator inside the PS4.
— flatz (@flat_z) January 20, 2018
How the PlayStation 4 emulator handles PS2 games is still mostly a mystery. For a while, it was thought it had to be tuned for each PS2 Classic released for it. However, now we know the emulator can run PS2 games without any particular modification. The tool, and the capability to run PS2 backups on PS4, is still in its very early stages, but PlayStation 4 modder Flatz published that they’ve been able to run Klonoa 2 and Shinobi backups on the console with no significant issues.
Since the PlayStation 4 is lagging behind the Xbox One when it comes to backward compatibility, it seems odd that Sony wouldn’t make better use of their emulator to at least let the system play PS2 discs. There may be some technical issues that make it unfeasible for Sony, but hopefully, we’ll see official support in a future update.