Right now the only way to play ps1 backups or different region games is to open the ps3 to do a disc swap. there is also some ps1 homebrew that should work with a disc swap. thereīs the yaroze ps1 homebrew and have also heard of an NES emulator but have never tried it.
The ps1 emulator for ps2 is on standby for the time being. The author, ffgriever, is working on another project, so itīs on hold for now. there is a beta but only a few trusted people have it. the info i have is that itīs not really playable at the moment. slow framerate and no sound. usb loading is supported though which is the only way we would be able to run it on the ps3 and because itīs ps2 homebrew, you would need a PS3 with ps2 BC to run it.
Only if it has 4 usb ports.