The Last Image Flipper? Is it one word or two?

goon, mods, drama, cornball? not necessarily in that order

Also, would it make sense to have the mods in their own nation? I think it does.

Goon. Mods. Shitpost. Cornball. Long ago, the four MSMG nations lived in harmony. But everything changed when the Goon Nation attacked. Only the Memer, master of all four elements, could stop them, but when the stream needed him most, he vanished. A hundred years passed and my brother and I discovered the new Avatar, a newgen named [placeholder]. And although his cornballbending skills are great, he has a lot to learn before he's ready to save anyone. But I believe [placeholder] can save the world."

Wait, who's going to be his team members? Who's the fire lord?!

Fire lord could be Andréw or Toady
Not sure who his team members could be but 32bit could teach modbending

Fair. Wait, which element is that. Also, Toady can't be in charge of anything unless it's a kingdom of these alts I keep hearing about.

True...
Maybe the story and characters wouldn't match up exactly

Oh. And which one suddenly attacks one day?

"everything changed when the goon nation attacked" could refer to the 10k rule being removed a while back but idrk

Oh, mayhaps.

Also, drama has a whole nation?

true...
could be shitpost nation instead ig if dramas translate into wars or something

That makes more sense. You have gooners, cornballs (and newgens), then normal shitposters.

Wait, who would be the Avatar? I feel like Chronolith would be the previous avatar, but I'm not sure who Aang would be,

Me neither.