Swap data, profiles, app on two Mac with Migration Assistant I make it easy: I have two MacBooks, all the data in MacBook A have to migrate to MacBook B and vice versa (so all the data in MacBook B have to migrate in macbook A as well). I want to do it with Migration Assistant. I already read that MI copies the files without deleting them. Do I run any risk or I can go smooth?
Migration Assistant works best on a cleanly erased Mac.


borrow/buy a drive large enough to back up Mac A
Time Machine Mac A onto drive and then disconnect the drive
Erase Mac A and install new OS
Migrate everything from B to A - connect the two to the same network or use Target Disk Mode
Erase Mac B and instal new OS
Migrate data from the backup drive to Mac B


Swap complete.