I saw something that I don’t think I was supposed to see yet about Turf Wars because it looks like another leak. Just a warning, a spoiler is going around, SO BE CAREFUL IF YOU DONT WANT TO BE SPOILED.
I actually remember reading an article from Bryke when they were asked the same question, and they said that Korra would win because she is the most powerful Avatar thus far. I think they said Korra was the most powerful, Kyoshi was next most powerful, and I want to say the next was Aang or Roku? I can't remember but I know for sure they said Korra then Kyoshi. And also that Korra was the shortest of all Avatars, and Kyoshi the tallest (with biggest feet!).