I cannot get a clean copy of my internal drive to an external one

Read carefully my last message , I did multiple times

Well, you stated you did, "Apple official restores." It doesn't matter how carefully one reads it, it makes no sense.

"Restore" as was used in the past no longer applies. You have to install the OS and then Migrate your data. This article about restoring from Time Machine is for the internal drive, not an external, but it is the closest thing available.

Restore your Mac from a backup - Apple Support

But, it references the Reinstall macOS article which is specifically about the internal drive. I think it should work for an external.

For the external you would need to install the OS onto it from that Mac. Cloning it will almost always fail. Once you have the OS installed and you successfully boot from it (have you successfully created a bootable external drive?), you would need to migrate your data. I have never done so from the internal drive, but I suppose it is possible. You may have to migrate from a Time Machine backup.

Did you try doing a clean install of the OS on the external drive, and then migrating your account and installing the driver

and software, instead of cloning?

Cloning a system drive is something that Apple does not want us to do. Instead one should only clone of migrate the data.

you do not indicate how you are "cloning" the drive. Are you using Carbon Copy Cloner? Downloading the OS from Apple and installing on the external drive? Also, why are you concerned about trying an update before installing on your "work" computer?

I don't know why it doesn't work on the external, I was just commenting on your use of the confusing term, "restore," and expecting everyone to understand what you really meant. Restore doesn't mean what it previously did, so it doesn't provide any clarity when you said you used the official Apple restores.

If you want people to understand what you did, post links to the official Apple support articles you followed.

Also, your question referenced a "clean copy" of the internal drive. That, essentially, is not possible anymore.

When a computer is told to boot from a certain HD, it does not treat that choice different than an internal HD and you know the internal works. And his doesn't make sense, but your external drive has a different name than the internal, could that be a factor with some memory within the hardware that requires a setting change on the external OS? You said you use Carbon Copy Cloner, ask them about this situation as there is an appearance that you do not have a fully functional copy using their software.

The only conclusion from this discussion is that the external drive copy somehow is different. Maybe it's the security policy, audio midi setup, some other setting or permission, whatever.