According to MCU Exchange, Clint Barton (Jeremy Renner) will drop the mantle of Hawkeye and become Ronin in Avengers: Infinity War. MCU Exchange provides information as to what this could entail, saying an event in the film will cause a shift in the character, leaving him “in a dark place.” Barton will then don a darker, possibly more brooding, mantle of Ronin.
In the comics, Barton takes over as Ronin, a sword-wielding samurai, around the time of Civil War and Captain America’s assassination, but eventually reverts back to Hawkeye.
MCU Exchange quotes a source they’ve used in the past who has proven to be correct in other scoops but does warn that because the film is months away, scenes and events could be cut.
Avengers: Infinity War is set to release in theaters on April 25, 2018
Avengers: Infinity War– Iron Man (Robert Downey Jr.), Thor (Chris Hemsworth), the Hulk (Mark Ruffalo) and the rest of the Avengers face their most powerful enemy yet, the evil Thanos (Josh Brolin).
Source: MCU Exchange