The A6 E-Tron is an all-electric version of the long-running Audi A6 sedan Will be based on the Premium Platform Electric (PPE) architecture used by the Audi Q6 E-Tron and Porsche Macan Electric Previewed by a 2021 concept Audi will unveil the A6 E-Tron, an all-electric version of the stalwart sedan, later this summer. This will be the second Audi…