Other mistake: Player 061 was female. But an eliminated photo showed a male participant with the same number.
What If... Captain Carter Were the First Avenger? - S1-E1
Other mistake: The premise of the first episode is flawed; "a single choice" should make the difference, the choice being identified as Ms. Carter not leaving the room to get in the observation booth. But in the normal timeline the booth is exactly where all the other characters were. In this reality everyone else is downstairs, with the German spy that inexplicably sets the bomb early. If anything, it's his bizarre, suicidal choice that matters.
Suggested correction: Except it was her decision to not leave the room that delayed the procedure and gave Heinz Kruger the chance to attack. And with her in the room, she is now given the chance to volunteer to take the serum.
How did her staying delay the procedure? Besides, in OTL the spy only triggered the bomb after he saw the procedure succeed, to know it works before stealing it.
Other mistake: When walking through the Captain America display at the Smithsonian, Brody and Sam stand in front of a Captain America mannequin next to his shield. The mannequin is wearing boots of noticeably different heights.
Other mistake: When Tarkin walks out of the Batch's quarters and the shock troopers follow him, the one on the right side of the door has his hands positioned to hold a blaster, but no weapon is present. (00:38:35)
Other mistake: Two FBI agents are speeding along a utility road trying to get to the airport and prevent a plane from taking off. They come across a closed steel gate in their way. They speed up the SUV and crash through the gate, and they get through as the gate breaks into many pieces. When their car gets to the airport we can see the SUV and there is not even a scratch on it.