So before, I sorted the characters into Harry Potter houses. Today I am sorting them into ATLA nations. I'm a big Avatar fan if you can't tell by my profile picture.

I also have a betta fish named Zuko.

So let's begin. I'll also be listing a few traits that I found associated with each group to kind of give examples. Feel free to comment if you agree or disagree with my placements.

Fire Nation: Stubborn, passionate, manipulative, independent, calculating, resourceful
Emperor Palpatine, Darth Vader, Kylo Ren, Jabba, Ahsoka, Darth Maul, Boba Fett, General Grievous, Qui-Gon, Lando, Snoke

Earth Kingdom: hard working, pessimistic, adaptable, stubborn, supportive, diplomatic
Din, Obi-Wan, Chewbacca, Han, Rey, Count Dooku, Poe, Jyn, Cassian

Water Tribe: even-tempered, perfectionist, loyal, judgmental, organized, sensitive
Padmé, Leia, Yoda, C-3PO, R2-D2, Mace Windu, Plo Koon, Shmi

Air Nomads: optimistic, restless, fun-loving, naive, charming, impulsive, imaginative
Grogu, Luke, Jar Jar, BB-8, Finn