Jackson Rathbone and Nicola Peltz at the KCA
This could be Aang's wanted poster, with the first sighting of the fake Asian characters. It does seem that they wanted the Asian-ness but not to explicitly tie it to one country, be it China, Korea or Japan. However, I think the classical script used in the cartoon did have sufficient distance, and it's not really a problem if the entire Avatar-verse uses it.
There are streamers/decorations in the background so the festival from The Deserter is probably in the movie. Wonder why Katara looks so happy about that wanted poster.
Nickelodeon's advertisement for the KCA after the break.