Only half of the original Avengers continue in the MCU. While Chris Evans and Robert Downey Jr. have returned to the franchise, that happens through different characters. Mark Ruffalo's Hulk seems to be the only original Avenger who could stay in the MCU for a long time, as the arcs of Chris Hemsworth's Thor and Jeremy Renner's Hawkeye are getting close to being wrapped up. With Marvel soon introducing the Fantastic Four and the X-Men, I believe that the MCU should recast the original Avengers, allowing the franchise to have all of its biggest heroes together at the same time.
