alright here goes:
Itachi and Kisame are both very powerful and kisame is known as the tailess tailed beast, and itachi well i dont know what to say, he is very powerful. But itachi needs a lot of chakra for his attacks and therefor he has kisame with him, with raw brutal power. Kisame is very powerful in general and has a few jutsu we have seen from him.
Well opponents Konoha: We got Kakashi, Tsunade, Naruto (SM, Ma & Pa, Toads), we also got many others. I dont know what to say about konoha shinobi, they are known to be very powerful and skilled.
Naruto can take on Kisame alone and Itachi, well naruto defeated pein, bu he got a little help from Hinata so actually he is not that strong in my opinion. Naruto with one person to assist him and naruto could beat them.
Kakashi, Tsunade can take om kisame and kill him, well itachi would win against kakashi with his Tsukoyomi, and tsunade would be a difficulty, since both of them are a lo of taijutsu, and she can use CR, though i the end itachi wins, but then we got naruto to kill him of.
Itachi's tsukoyomi and other powerful jutsu take tons of chakra, and as seen in sasuke vs itachi he used amaterasu and tsukoyomi and thats it and one firestyle and genjutsu, itachi wouldnt win.
Danzo would not interfere with the fight, since he wanted power, and well if we count in naruto and the others, they could take on both of them, while well danzo could do what ever pleased him, so i dont think danzo would fight, since its an oppertunity to take over as the Hokage, like in the manga when tsunade was in a coma after the fight against pein.
State: Itachi and Kisame would be killed, by 3 people and toads.