The Falcon and The Winter Soldier is where two of the most skilled fighters in the MCU will team up to fill in the gap that Captain America has left following his retirement, Sam Wilson aka The Falcon, and Bucky Barnes aka The Winter Soldier.
After the events of Avengers: Endgame, Captain America took the responsibility of putting all the stones they borrowed in their proper timelines but did not come back as expected. Captain America made sure his return will be worth it as he decided to stay in the past and reunite with Peggy Carter to finally make it to the dance that he never got the chance with her. Now old and gray, Captain America seemed to have the time of his life with his love.
Because of this, Captain America has to pass the baton of the responsibility for someone else to continue the legacy that Captain America had shaped through the years he held the shield and gave the shield to Sam Wilson, who's surprised as to why he was the one chosen by Steve Rogers himself. However, while he is now the holder of the shield of the cap, there was no showing that Sam Wilson agreed or that he would be Captain America.
Bucky, who seems to have agreed with Steve the whole time, didn't contest and accepted that the new wielder of the shield is Sam. Bucky took a look in Steve's eyes before he traveled back in time and he seems to have an idea that Steve will not be back through the machine he went into.
Both being the best friends of Captain America, Sam Wilson and Bucky Barnes will take on an adventure that will take their abilities and patience to the test in a world where they carry on the torch of Captain America in upholding what is right and take on Helmut Zemo and the anarchist group, Flag Smashers.
Is The Falcon and the Winter Soldier Canon?
Absolutely! The Falcon and the Winter Soldier is canon in the MCU. It's all there, all given, no questions asked. Their storylines haven't changed over the years and they continue what has already been started. The Falcon And The Winter Soldier will show the lives of the character in between the movies and give the viewers a glimpse of a day in the life of a superhero.
The Falcon And The Winter Soldier is one of the various limited series of the Marvel Cinematic Universe which will be airing through Disney+ forming part of Phase Four of the MCU.
Anthony Mackie and Sebastian Stan will reprise their roles as The Falcon and The Winter Soldier and they will be joined by familiar faces from the Captain America Trilogy, Emily VanCamp will be back as Sharon Carter aka Agent 13 and Daniel Bruhl will suit up as Helmut Zemo.
The Falcon first appeared in Captain America: Winter Soldier as a former US Airforce pararescue airman who left his duty after his partner died and focused on helping veterans cope up with post-traumatic stress disorder. When SHIELD was confirmed to be infiltrated by HYDRA, Captain America didn't know who to trust and found Sam Wilson surprising Steve that he dons the suit of The Falcon.
The Falcon pledged his alliance with Captain America and was then recruited to be part of the Avengers after the events of Avengers: Age of Ultron. The Falcon has always been there, loyal to the team, lending a hand to whoever needs it. When the Sokovia Accords were put in place, The Falcon sided with Captain America.
Over the years, Sam has always been there and he seems to be the right-hand man of Captain America. Now that Captain America is in his retirement, he is expected to take the baton and carry the legacy of the shield of Captain America.
Meanwhile, Bucky Barnes first appeared in Captain America: The First Avenger. He is the best friend of Steve Rogers and he belonged to the 107th Infantry Regiment during World War II which was captured by HYDRA for the experiment of Arnim Zola. Barnes was later on rescued by Captain America and they plan to take on the Red Skull when an ambush on the Austrian Alps ensued leading to Bucky's presumed demise after falling off the train hundreds of feet beside a mountain.
Later on, it was revealed that Bucky survived the fall but lost his left arm. He was found by HYDRA and was brainwashed. He became HYDRA's hitman, there to eliminate everyone who stands in the way, including the parents of Tony Stark. He was hailed as The Winter Soldier, one with a metal arm, and his life is prolonged through cryogenesis. When he attacked SHIELD in Captain America: Winter Soldier, Steve Rogers was dumbfounded when he learned that he's Bucky.
True to their words, "to the end of the line," Steve did not give up on him and later on sided with them and has been in the Avengers ever since.
Captain America is retired and Bucky will be on the side of the new wielder of the shield, Sam Wilson. Though it is possible that Bucky would also wield the shield of Captain America, that would be for us to find out as we tune in to the canon series of The Falcon And The Winter Soldier.