Pakku

Froakie: it is a water type pokemon, it represents Pakku, the reason why I chose it is because the white foliage that it has on its body reminds me of Pakku's hair, and they both have bald heads :).

Bumi

Conkeldurr: it is a fighting type pokemon, the reason why I chose it for Bumi is because they both have an old appearance but they are very very strong and the pillars of their hands represent their earthbending.

Jeong Jeong

Turtonator: it is a fire-dragon type pokemon, the armor on its head reminds me of the shape of Jeong Jeong's hair, its type represents Jeong Jeong's firebending and the two can be explosive and devastating.

Piandao

Aegislash: it is a steel-ghost type pokemon, it represents the mastery of Piandao with the sword and if you remember Sokka (his pupil) I gave honedge that is the anticipation of this pokemon.