Canon has just registered a new camera code DS126821, this new camera has LP-E17 battery. This battery is compatible with EOS M3, M5, M6, M6 Mark II, Rebel SL2, Rebel SL3, Rebel T6s, Rebel T6i, Rebel T7i, and 77D. So this new camera could be a new APS-C mirrorless camera or DSLR camera.
According to latest rumors on CR, a pro/high-end mirrorless camera with both RF mount and EF mount is in the works. This means you will be able to mount both RF lenses and EF lenses without the use of an mount adapter. This would be a great news for Canon shooters.