(Altered World state)

This is a fusion of the two some characters will exist some characters won't the ones that won't most will not come from Korra. Korra and Asami as well as adult versions of jinora, ikki they'll be in it( but it's up to the writers discretion to figure out how they're going to be in it)

For starters Aang was never frozen in the iceberg and prevented the complete destruction of the Airbenders he was never able to defeat the Fire Nation throughout the Hundred Year War due to the fact that he stayed true to the Airbender philosophy of all life is sacred he never met the lion turtle so he never learned energy bending

( note that all characters that you want to have sex scenes with should be 18 if they are not you should age them up another thing to note due to angs interference the Fire Nation isn't nearly as far in world domination as they are in the Canon. Another note you and make your character a non-bender as well)

(I did some research on some of the characters of Avatar and in the Canon out of the main female characters the youngest is toph who is 12 the rest are either 14 or 15)