Why? Has SR7 teased reused character designs from ATLA in BoB2? With the exception of Korra every character from Themyscira who could appear in BoB2 would be in their late 80s. Themyscira has a handful of lookalikes, one of which is based on April O'Neil from the 80s/90s TMNT cartoon, it's very likely he's simply using Themyscira to establish his BoB2 art style.
Don't get me wrong, I fully expect BoB2 is going to be chock full of the frankensteined nonsense that modern Something Unlimited is but the designs might not be reused outside of Korra unless SR7 has contrived something to justify his laziness in the game.