I don't think that copyright would apply because the EV1 design largely serves a functional purpose, and design patent infringement would face an uphill battle for the same reasons. For copyright of a "useful article" the functional aspects of the design cannot be protected, only the artistic ("separability"). For design patents, elements of the design that are dictated by function cannot be protected (N.B., there is some nuance there for alternative designs). The strongest exposure for EV1 replicas is probably trade dress, and the iconic design ("secondary meaning") of the EV1 should strengthen those claims.

Also, trademarks do not need to be registered to be enforced, although it is wise to register them.