The Falcon and the Winter Soldier are already bursting to the brim with new characters introduced to the wider Marvel Cinematic Universe. These include characters mostly on the villain front, with new terrorist organizations like ULTIMATUM and maybe even the formation of The Thunderbolts to oppose Sam and Bucky.
Daniel Brühl's Zemo and Georges St-Pierre's Batroc the Leaper are already returning in The Falcon and the Winter Soldier. However, there are years worth of older characters that could see a return in the streaming series. One of the show's writers has come out to state that fans will, in fact, see more familiar characters returning on the show, but not in ways they'll expect.
While speaking on the Script Apart podcast (via Empire) about his original screenplay for John Wick, writer Derek Kolstad also talked about The Falcon and the Winter Soldier. Kolstad mentioned that the show would bring back earlier characters introduced in the MCU.
“What I will say is that there are characters from the earliest Marvel movies that are coming back. We’re layering them in and reinventing them in a way that’s gonna shift the storytelling structure. It’s fucking awesome."
WHAT THIS MEANS
When Derek Kolstad describes that these returning characters would be reinvented, it sounds very much like they won't be the same from their last appearance in the MCU, which could mean anything from their appearance, motives, and personality will be adjusted.
One of the more likely candidate to see a return is Toby Jones's Arnim Zola, who debuted in Captain America: The First Avenger in 2011. Jones was last seen in this franchise on film in Captain America: The Winter Soldier and on television as a cameo in Agent Carter. Fans have yet to see this character take their final form from the comics as an autonomous robot, so seeing Zola return in The Falcon in the Winter Soldier with a robotic chassis would be a treat for fans.
Other characters from "the earliest Marvel movies" who have a decent chance of making an appearance in The Falcon and the Winter Soldier and who haven't been heard from in a while include Abomination and The Leader from The Incredible Hulk, Sam Rockwell's Justin Hammer from Iron Man 2, and some of the Howling Commandos (who could be primed for flashback scenes fighting alongside Bucky).