Ruby had returned and will prove once and for all that her scythe abilities are not to be underestimated. She can fight at high speeds and even has aura to back her up. Her gun extensions make her a very versatile fighter as well. Ozai’s elemental blasts likely won’t cut through her aura and either way it would simply be hard to land a blow thanks to her speed. Ruby Rose wins.
Suggested by Eric Zuko and Ozai are both powerful fire benders. While Zuko always seemed like the big rival of the series who would go on to be the very best, it seems like he never quite surpassed Ozai. That, or he never got to show off any abilities that would put him above the older bender. Ozai’s physical abilities are just as impressive as his fire and that allows him to dodge very fast attacks and endure others. Zuko just doesn’t have that same level of physical ability to support his elemental abilities. Ozai wins.
Suggested by Eric Kuvira is a metal master who is very adept at manipulating it to her will. She can tie opponents up with the metal or hit them with direct attacks. Unfortunately this matchup does not work in her favor as Ozai’s incredible fire abilities will completely nullify any advantage that she may have had. Any metal that she tries to use will be easily melted by his attacks and Ozai also has a lot of physical power to fall back on. Ozai wins.