i think KDbest can help on this point im remember that he has make a edat tool.
but the ps2 classics edat is very smaler from the ps1 classics edat.
this are the edat of max payne ps2 classics
and then we have to look how the enc are encryptet. i hope there will come sone a solution to build our own ps2classics pkg from a retail Ps2 disk like the psx2psp