Ok so I realize now how big the bag of worms was that I opened with this lmao. Now I'm loving all the idea's you all are giving me and I sure am going to have huge lot of work to do on the next chapter. Since nearly everyone is in favor of Naruto or both of them getting the sharingan. One thing about it is that I won't be having Naruto gain power over more tails because of having the sharingan or using Kyuubi's power in such a way. I'm in favor of Naruto having his own abilities instead of the all out brute fighting style of the Kyuubi shroud. I know having a Mangekyo sharingan isn't Naruto's own power but it would take some level of skill to use as well as strategy unlike Kyuubi just purely flooding Naruto's body with chakra until it's so strong that nobody can deal with it. This leads to the problem with making Naruto godlike. Now no matter what, Naruto IS in godmode both in my story and in canon because as well all know, neither me nor Kishi are going to kill off Naruto meaning he can't die aka godmode. Still the fights have to be believable and not completely lopsided, which becomes increasingly tough with him having Mangekyo. So we'll have to come up with some abilities that are not completely overpowered, but also that are realistic. One move I really don't like is Amaterasu, I mean being able to just look at something and make it go up in flames that can't be put out for seven days and nights is a little too overpowered for me. I mean if Itachi in canon was a good guy he could have used Amaterasu on all of Akatsuki and due to the jutsu's overpowered nature, kill all of them and they literally couldn't do anything. At the very least he could have done it to Orochimaru. It just seems like it was made way too overpowered and it has some obvious flaws because of Kishi trying to balance the whole power struggle out. Anyways, it's hard to make a fight believable when one of the shinobi has a jutsu of that caliber in their arsenal so I don't want any of that lol. Now I'm thinking since they are Itachi's eyes, and if I do choose to give them to both Naruto and Yugito, that one of them could get Tsukuyomi and the other Susano'o. So that leaves a total of four jutsu's left to fill which we will all have to come up with.

SLIGHT SPOILER WARNING FOR MY STORY (Concerning the Sharingan and what I might do with them)

So ya I warned you, anyways, my original idea when I decided to maybe give someone Itachi's eyes was nearly identical to what Infinite Freedom suggested. So my idea was to give Naruto the eye's and due to the relation of Uchiha, Mangekyo and Kyuubi, that Kyuubi would be able to incorporate the sharingan into Naruto as if he were an actual Uchiha. Also since it's a Mangekyo transplant that they would also become Eternal Mangekyo's so that Naruto's sight wouldn't deteriorate. Now I actually overlooked the possibility of Yugito also getting the Sharingan but like that idea. So as Infinite Freedom said, I could give each of them a sharingan and just like how I would have had Kyuubi integrate sharingan in Naruto, Nibi would do the same for Yugito. I don't like the whole one eye Kakashi idea though so I would have the two demons kind of alter their DNA to handle the eyes giving them sharingan in both.

Now the excuse I can use to pull this off is how Madara is after all the Biju to complete his sharingan, meaning that there is a relation between the demons power and sharingan. We don't know exactly what it is but since it's a fanfiction and it hasn't be shown yet I can use it to my advantage and make up a legit reason of why it's possible. So to sum it up I would be giving them both Mangekyo in both eyes and giving each of them either Tsukuyomi or Susano'o and then coming up with two more Jutsu each.

So if you like this idea let me know, if so what I need are idea's for possible jutsu candidates and also any names you want to throw out there that sound cool for them lol.