Mazda recently filed a patent showing an EV with Rotary engine. I suspect this is direction they would go in if the RX-Vision concept becomes reality.
"The second patent is for an engine start-and-stop system, but specifically for rotary engines. The system is designed to shut off a rotary engine when not needed, much as modern piston engines do. It also stops the rotor in a position that closes the intake port to ensure no fuel or exhaust emissions slip out through the intake tract. This is necessary since there are no valves in a rotary, and air and exhaust come through ports that are "opened" and "closed" by the rotor itself. The patent also describes the possibility of firing a spark plug after the fuel has been cut to eliminate any leftover fuel emissions. This system would theoretically improve a rotary engine's fuel economy and emissions significantly, which would be a boon as those are two of the rotary's major weaknesses."