One week?

That is way too short to experience all the fun and joy coming your way.

The fun begins all over again whenever you start trying to make changes --- like say for a system upgrade. It's better to just wipe everything clean and start over.

"The location of the Fn and Control keys are swapped. And, of course, neither computer allows re-mapping the Fn key"

On MacOS: Settings -> Search for "Customize Modifier Keys"

The Fn key is what they call the "Globe" key now. You can map any of the five (including caps lock) keys to anything.

My solution - use Linux for servers, use Mac OS for your client. Also, treat your servers as cattle.