He would overwhelm Leonard and Hearns, though each would probably take one of 3 three fights from him. Duran was old by the time he got to 160. I'm not sure he'd have the basic punch output. hagler would beat Jake on points.
LaMotta Duran would be absolutely brutal. Trust me there would be no "No Mas" moment. But there would be a mess to clean up after the fight...I have no idea who would win but it would be savage.