Easter Eggs You Noticed That Few Others Did

[LordLeviathan]

For me, it was Spider-Man's first appearance in Endgame, swinging under the bridge, which was a clear callback to the 1966 cartoon theme montage

less an easteregg more of a funny writing coincidence.
the geographic location loki and thor have a chat in the forest might be the Odenwald(yep the neme of the forest means Odin's Forest/Wood
https://en.wikipedia.org/wiki/Odenwald

[babyblob]

In the League of Extraordinary Gentlemen when they are in the conference room there is a piture hanging on the wall that shows a character dressed as a scarecrow. This is one of my favorite literary characters known as The Scarecrow. The Scarecrow is a British character who is a man named Dr Syn a Vicor of Dymchurch and former pirate who with his assistant Mr Mipps Aka Hellspite started a gang of smugglers to fight King George the 3rds taxation and other forms of tyranny. Thee was a Disney movie in the 60s called The Scarecrow of Romney Marsh. I loved that movie as a kid. my dad had it on tape and we would watch it for hours.

[Zero Hunter]

There was an episode of Farscape where Scorpius is tourturing John and they are talking with each other. John says "Time wounds all heals" at one point which is the title of a Nick Lowe song. Unless your a Nick Lowe fan your going to totally miss that one.

[Arfguy]

I was pretty amazed when I was re-watching Captain America: The Winter Soldier (2014) where Natasha shows Steve the bullet wound, that you could actually see the "Graduation Day" scar that would be alluded to in Avengers: Age of Ultron (2015).

Meaning, while Joss Whedon was working on AoU, the creative people behind TWS wanted to throw a little extra bit of "pay attention" in their movie, which would come out first. Small stuff like that is where the MCU gets it so perfectly.

[Midvillian1322]

I'm sure everyone on here got it. But when I watched Zombieland 2 in theaters I was the only one who laughed at Woody Harrleson writing a pardon for Wesley Snipes. Guessing most people in the theater didn't know his legal issues and the rest for sure didn't know him and woody are best friends. Or at least one other person woulda gave a cheap chuckle.