I found an Italian website that offers this and other procedures. To automate the modification, it suggests pressing SHIFT+F10 and then using the built-in Windows curl command to download a simple cmd script:
https://www.ilsoftware.it/focus/windows-11-con-account-local...
The cmd file can be run with the no-oobe username option, allowing you to choose the name of the local user account to be created. I hope this is helpful.