Also ich wollte mich an diesen PLan halten aus einen Beitrag aus drivetheamericans.com

For those of you who want to know, here is the basic process for selling a US plated car to a foreigner in South America.

The seller magically finds a buyer. (They can be from anywhere, except Argentina.)

The seller creates a bill of sale for both parties. (it is signed and notarized).

The seller signs the title and hands it over to the buyer.

The seller and buyer go to a notary public (i.e. Lawyer) in Buenos Aires and have a power of attorney created. This notarized paper states simply that the seller has permission to drive the car everywhere for an unlimited period of time.
Seller and buyer go to a customs office in Buenos Aires (or cross a border). Here the temporary vehicle permit is transferred from the old owner to the new owner. This allows the old owner to leave the country. And gives the new owner the correct paperwork to legally be driving in Argentina.

The seller reports the car sold to the Department of Licensing in Seattle. This removes all responsibility from the seller for things like traffic tickets.

This is all that needs to happen for the old owner to no longer be legally responsible for the vehicle and for the new owner to drive it legally anywhere in the world.

MAl schauen ob das so klappt