Recently samsung galaxy M51 is listed on the official samsung website as SM-M515F.
previously SM-M515F is also listed official samsung russia website.
as per leaks and rumors Samsung Galaxy M51 might have 7000mah battery and snapdragon 675 as a processor. and some of the camera improvements are going to provide than the previous predecessor.
Samsung Galaxy M51 is might carry a 6.7″ Infinity-O punch-hole display. The back will sport a fingerprint reader alongside a four-camera array with a 64MP main shooter and 12MP ultrawide camera.