Unlike in our world, in the ATLA-verse brown eyes are rare.
As we all know, the eye color usually corresponds with the character's nationality.
Watertribe = Blue
Fire nation = Amber or grey
Earth kingdom = Green
Air nomads = Grey
Even Toph, who is blind, has a green tint to her eyes.
So, I tried thinking of brown eyed characters since there aren't that many. Most of these seem to be EK but it's definitely not exclusive.
Here they are below the cut, let me know if I missed any.
Jet.
Meng.
June.
Kei Lo.
Longshot and possibly Smellerbee, Pipsqueak and The Duke. They're drawn black, (except for Longshot's in some scenes) but very, very dark brown is the only realistic color they could possibly be.
Song and her mother.
Thanks @atla4art for pointing out Mai's seem to be brown. Like a sort of grey tawny color.
[ID:A screencap of Aang, Pipsqueak, & The Duke from Avatar: The Last Airbender. They all have closed-eyed, wide grins, laughing by each other. Pipsqueak has a hand on Aang’s back. End ID.]
Sorry if tumblr deepfried the quality, I tried to get close ups. And sorry about the shadows or light on the pages, I couldn't find a light source good enough.
ⓘI added image descriptions (ONLY ON THE CLOSE-UPS WITH TEXT) incase you have a hard time reading the pages due to tumblr compressing the images.
No matter what canon explanation they might give for how the freedom fighters got their names, I'm sticking with my personal headcanon that Jet (nick)named them.
It seems more emotionally resonating.
So I headcanon that they had names before meeting him. He himself likely named himself "Jet."
The names you hear in the show seem like nom de guerre to me.
I already gave Jet one here .
Here are the rest, I hope I got the meanings right.
Thinking about the fact that no one in Jet’s gang had real names which is kinda a way to show how war erases identities. Like these kids are from villages that have been burned to the ground and completely wiped off the map. Their homes and families are gone and so are their names. Them not having names shows how the fire nation took everything from them even who they are. That’s the horror of war. Not the occupied cities. Not the maximum security prisons. Children who don’t have names because nobody is left alive to remember them.