More progress in the PS4 scene!
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, wrapped into a simple program.
So far it's been reported to have...
free-ps2-pub-gen - A Tool to Create PS2 Packages Working on PS4 4.05