If you’re splitting up accounts or setting up a new machine, the process is similar.
Apple makes it relatively painless to migrate data on one Mac to another. But you can also selectively migrate and split up multiple users on a single Mac into users across multiple Macs. You would do this if, for example, you have kids on a shared computer who now own their own, or if you’re leaving a job and want (and are allowed) to take your home directory with you.
Migration Assistant is the app you use to perform a user migration. It’s found in the Applications folder’s Utilities folder. This flexible software can work in a variety of ways to transfer all or part of the applications, user files, and other settings on one Mac to another. You can start from Time Machine backup, another Mac, or a Mac drive configured as a macOS startup volume—including a disk image backup.
The simplest way to shift one user to another is when you can put both Macs near each other with Wi-Fi enabled. (ethernet, FireWire, and Thunderbolt used to be options for connecting Macs for migration, but Apple no longer recommends these.)
Assuming the new Mac is set up from scratch with at least one user, here’s how to use Migration Assistant to move a user from one Mac to another.
Read more at MacWorld.com