The upcoming PlayStation Classic has been found to use the open-source PCSX ReARMed emulator to run its games. The emulator has been developed by retro gaming enthusiasts, not Sony. It's curious that Sony opted to use an emulator rather than develop their own system for the retro console.
https://www.notebookcheck.net/The-PlayStation-Classic-uses-the-PCSX-ReARMed-emulator.358381.0.html