We've already mentioned Comic-Con, but I don't even think Avatar will be at D23? When they announced all the big studio panels, they mentioned a Disney Live-Action/WDAS/Pixar panel on Friday, and then a Marvel/Lucasfilm panel on Saturday. Avatar doesn't fit into any of these camps and they didn't say a word about any 20th Century Studios panel. Maybe it could get lumped into the Live-Action stuff with Little Mermaid and whatever, but it seems Avatar could be MIA, which is super weird.
It could be Disney not wanting to push them, but that doesn't make any sense, since they already have the theme parks, the first movie is on Disney+, there's a Neytiri profile picture, etc. They clearly are pushing Avatar as a core part of the Disney family. Maybe James Cameron wants his movie promoted away from everything so he has all the attention? Maybe that's it, but it would still be really stupid of him not to hype up Disney fans. Hopefully I'm proven wrong and Avatar's ready to go for D23.