Sasuke and Itachi win this. Itachi doesn't need to pull out his Mirror yata and Sword Totsuka Susano'o. He can be housed inside Sasuke's final Susano'o. Sasuke can summon Aoba and sit on top as well. The summon can attack Madara as well. Sasuke can use Enton Sword to damage Susano'o and Itachi can engulf the whole field with Amaterasu which can be spread with the sweep of his gaze. If he uses Flower Tree world then it'll only prep Kirin that much faster.
Itachi's V4 Susano'o was obliterated with Kirin and it burned his skin as well. Madara's form would get damaged as well. Then Sasuke can Itachi can attack simultaneously. Sasuke can use Enton arrows and Itachi can create his own V3 Susano'o to bombard Madara with Yasaka Magatama. All of Madara's attacks will be tanked by both Susano'os' or they will surely be able to sustain enough damage to last in a fight. By this time, Kirin can be used again, along with the additional attacks to create a gap in Susano'o. Once that happens, Itachi can easily pull out V4 and seal him.