Final Fantasy I: The new dungeons from the Dawn of Souls version remain and the music tracks from boss battles were changed to the tracks of the games the new bosses originated from, adding five new tracks.

Final Fantasy II: The Arcane Labyrinth featured new bosses as well, but it is unclear how many, if any, new tracks were added.

I don't think an OST of this exists, and I'm not sure if these extra tracks were ever released elsewhere, but if someone could find them, even gamerips, I'd appreciate it.

I don't believe there's any new tracks for FFII 20th Anniversary.

I do have the FFI extra tracks (not my rip): https://mega.nz/#!PABDXAzZ!OMpd-z-DGhOU2LjMM491E_mpA8xSTotXnX0_sqsns7c

Thanks! Good stuff! As expected of Square Enix's sound team.