I'll start with the one someone brought up, then some that caught my attention.
#1 Civil War:
Barton: We haven't met yet. I'm Clint.
T'Challa: I don't care.
In Endgame, T'Challa calls Hawkeye "Clint".
#2
(Gi)Ant-Man grabbed War Machine by the leg in Civil War.
(Gi)Ant-Man grabs War Machine (along with Rocket and Hulk) to protect from collapsing Avengers HQ debris.
#3
First Avenger:
Bucky: Don't do anything stupid till I get back.
Steve: How can I? You're taking all the stupid with you.
In Endgame, it's flipped around with Steve saying Bucky's line and Bucky saying Steve's line.
#1 Civil War:
Barton: We haven't met yet. I'm Clint.
T'Challa: I don't care.
In Endgame, T'Challa calls Hawkeye "Clint".
#2
(Gi)Ant-Man grabbed War Machine by the leg in Civil War.
(Gi)Ant-Man grabs War Machine (along with Rocket and Hulk) to protect from collapsing Avengers HQ debris.
#3
First Avenger:
Bucky: Don't do anything stupid till I get back.
Steve: How can I? You're taking all the stupid with you.
In Endgame, it's flipped around with Steve saying Bucky's line and Bucky saying Steve's line.