Ventura docs for M2 Macs in this comment: https://gist.github.com/henrik242/65d26a7deca30bdb9828e183809690bd?permalink_comment_id=4555340#gistcomment-4555340
Old Monterey docs in this old revision: https://gist.github.com/henrik242/65d26a7deca30bdb9828e183809690bd/32c410e3a1de73539c76fa13ea5486569c4e0c5d
Solution for Sonoma: https://gist.github.com/sghiassy/a3927405cf4ffe81242f4ecb01c382ac
I hit this error and couldn't find a way around when attempting to use the external SSD as a Startup Disk:
Even if I didn't have the previous error, I hit another one when restoring my internal SSD from the external SSD preinstall (tried with internet and without):
Then if I proceed even after the above two errors, I find that 95% of the used storage was copied to the internal disk but after attempting to install macOS on the internal disk, I get this error about halfway through:
Tried both macOS 12.6 and macOS 13.4. Both have identical outcomes. External SSD install performed via non-DEP M1 MacBook Air.
TL;DR: Seems your method simply doesn't work since there's too many blessing or sealing mechanisms macOS performs.