How does that work when an individual sells a car?
If it's to a stranger, I go with them to the BMV/Title office, fill out the necessary blanks on the title in front of the notary, have it notarized, and keep my plates. The buyer then has to get temp plates right there.
Now, if it was a sale to, say, my brother, I could have my neighbor the CPA witness and notarize the title, then let my brother take the title and the car with my plates on it for up to 30 days until he gets to the BMV. Then I get my plates back.