Can MacOS High Sierra or Mojave run in Rosetta 2 on an M1 MacBookPro?
Have few good old apps that are not ready for M1 or any MacOS above High Sierra or Mojave.
Can those OS be load and run in Rosetta 2 on an M1?
No. You cannot run a version of macOS older than what came preinstalled in a Mac, so M1 Macs must run Big Sur or later. Rosetta 2 will run Big Sur-compatible Intel apps.