Captain America: Brave New World | New Trailer 4

Red Hulk makes his MCU debut in Captain America: Brave New World, but previous events would appear to make this impossible. In the MCU's Captain America: Brave New World, Harrison Ford takes on the role of Thaddeus "Thunderbolt" Ross, replacing the late William Hurt, who first portrayed the character in The Incredible Hulk. Ross has been a significant figure in the MCU, playing the aggressive military leader obsessed with controlling or eradicating the Hulk. With his return in Brave New World, there's a strong possibility that the MCU may finally deliver on Ross's transformation into the Red Hulk.
In Marvel comics, General Ross becomes Red Hulk after being exposed to gamma radiation and a variation of the Super Soldier Serum. This parallels Bruce Banner’s origin as the Hulk in the MCU, where Banner's transformation resulted from an experiment to recreate the serum that turned Steve Rogers into Captain America. However, bringing Red Hulk into the MCU isn’t as simple as recreating his comic book origins. The MCU timeline has evolved its narrative, creating hurdles that need to be addressed before Ross can become the monstrous Red Hulk.