In The Falcon And The Winter Soldier, we see that the Smithsonian Institute's exhibition dedicated to Steve Rogers includes sections on Bucky Barnes and Isaiah Bradley. At this point, the opportunity was lost to have a section dedicated to Peggy Carter, where they would describe the adventures she experienced in her own series, Agent Carter.

In Black Widow, the Red Room is formally introduced, revealing that Natasha Romanoff and Yelena Belova were trained to become Black Widows. At this point, the opportunity was missed to mention that the Red Room has existed since the 1940s, as we saw in Agent Carter Season 1, where we see one of the first Black Widows in history, Dorothy Underwood.