I know EMS Sasuke is stronger or equal to KM.But he can create a maximum of 11 clones, he can lower that amount to five and take each Kage on instead of making weaker clones.I think Km can solo high diff while Sasuke loses if he doesn't do anything about Onoki or if he's in the desert since Gaara can use the sand under Sasuke to drag him out.
Bm Naruto shouldn't be discussed he's to broken in teams.
What if Sasuke gets the Kyubbi cloak, do you think he can solo?
Clones might make things hard but I think the five kages can defeat KM Naruto high difficulty. Sure Naruto would win if he manages to separate them and take them on separately but with team work, the five kages could dispatch those clones. I guess it also depends on the starting distance. Once Onoki and Tsunade launch that huge jinton, Naruto and all his clones get atomized.
Naruto's best chance would be to take Onoki out but he can fly and allow the other kages to distract the clones. For example, the Raikage could keep them all busy with his speed because Naruto clones don't necessarily display KM Naruto's top speed. Mei wouldn't have much of a chance at making much of a distraction though and Gaara won't have the time to create a large amount of sand.
I do believe that if the five kages were to go all out from the start, Ay, Mei and Gaara would have to be sacrificed for Onoki and Tsunade to beat Naruto.