Electric cars and coupes are described on different grounds. Electric identifies how a car is powered; coupe describes a body style, traditionally with two side doors and a relatively low roof. A coupe can be electric, and an electric car can have several different body layouts. The terms do not define opposite kinds of vehicle.
For a useful comparison, separate the electric powertrain from the doors, seats, roof, and luggage opening. Charging and energy recovery are powertrain differences. Rear-seat access and loading convenience are body differences. Ride comfort, performance, refinement, and ownership cost depend on the actual models rather than either label alone.