Kakashi is my favourite character in Naruto. So I would be a bit biased but please bear with me.
(Note:- I assume that both the sharingan in Kakashi’s eyes are Obito’s)
Lets Compare the two:-
(From third official databook)
Kakashi’s taijutsu level was said to be on par with Might Guy(without 8 gates). His constant rivalry with Guy indirectly helped him copy several of guy’s moves and improve his taijutsu a lot. He has been seen easily fighting ninja’s like naruto, sasuke, kakuzu, hidan, etc. His speed and reflexes was also said to be really impressive.
Itachi was very proficient in taijutsu as well but it was not his preferred fighting style. However his speed and reflexes were enough to surprise kakashi and sasuke as well
Itachi and kakashi face off
So after having sharingan in both eyes, if the fight came to hand to hand combat, i would say Kakashi would win.
Not his preferred choice. But still he would counter most high level genjutsu’s easily. This can be best seen when he fights off Obito to a genjutsu stalemate in the kamui dimension.
Itachi is hands down the winner in this category!!! I bet apart from madara’s infinite tsukuyomi, this man would be the most feared ninja just because of his genjutsu abilities. Although the databook suggests only 1 point more than kakashi, he is wayyyyyyyy ahead of him in genjutsu. His mastery of genjutsu could be seen when he trapped kakashi in tsukuyomi and tortured him for which felt like 3 days and which was over in just few seconds in the real world. Also he was able to use and program shisui uchiha’s kotoamatsukami to free himself from kabuto’s control. He also used Izanami on kabuto and forced him to stop the impure world reincarnation tchnique.
Itachi using tsukuyomi on kakashi
Itachi is clearly the winner in this category. Even if kakashi has sharingan in both the eyes, he may be able to resist Itachi’s genjutsu to large extent but he could never be on the offensive.
While Itachi’s is most proficient with genjutsu, Kakashi is a master of ninjutsu. (I’ll talk about their sharingan abilities in another section). At the end of the manga, kakashi is shown to posses all 5 elemental nature transformation and yin style and yang style that too without any body modifications(eg: kakuzu, fuka), rinnegan(eg: nagato, obito, madara and sasuke), tailed beasts(eg: naruto). He can use elements like water and earth to beat the sh*t out of ninjas like zabuza. And he had a natural affinity for lightning style. He created the chidori and later lightning blade. This jutsu was so strong that it has become sasuke’s most preferred ninjutsu. And kakashi was able to defeat several reincarnated seven ninja swordsmen of the mist and also sever a jinchuriki’s chakra arms using this technique. He can also use shadow clones as well.
kakashi’s lightning blade.
kakashi’s water dragon jutsu
Itachi’s ninjutsu is also on par with kakashi’s. He posses fire, water and wind elements. His fire style is a testament to his uchiha heritage. He can use great fireball, and phoenix fire jutsu and even combine them with shurikens to make the attacks even more deadly. His water style skills are also pretty good and he can use water dragon bullet. Also he can use shadow clones which disperse into crows(an ability unique to itachi).
itachi using great fireball jutsu
itachi using phoenix sage fire jutsu along with shurikens
For me, Kakashi is the winner in this category. Because, he has a vast and better arsenal of ninjustu than itachi’s.
Other categories from official databook includes:-
Both are equal in this category. Both of them knows sharingan’s abilities and can predict what the other will do. So a draw for both of them.
Although the databook suggests Itachi is faster compared to kakashi, but as seen in the fourth shinobi world war, he was able to blitz pass kaguya and evade several of her attacks and also fight on par with obito(who was trained by madara and had the rinnegan as well as the sharingan).
So i would say, Itachi may win in this category but the difference would be very minimal.
It was said that itachi suffered from an unknown illness thus he couldn’t use jutsus like amaterasu and tsukuyomi very frequently and hence he had a very low stamina. Similarly kakashi also suffered adverse effects of using his sharingan too much and required bed rest for a week after just 2-3 uses of his kamui. So both of them are more or less same in terms of stamina.
both are equal in this category.
That brings the total scores like this:-
This data was entirely from the third official data book.
You can check these here:
Now the main comparison: Their Sharingan abilities!!!!
(note: this is my own view and not from some databook.)
Kakashi had only one sharingan but he was said to be extremely proficient with it. His sharingan abilities earned him the title of “Copy ninja”, and he was known in all 5 great shinobi nations. He can copy an opponent’s jutsu and use it against him even before his opponent can use it. So kakashi with both sharingan would be more powerful but this would drain his chakra faster.
Itachi’s didn’t show the ability to copy an opponent’s jutsu, but since he is a sharingan user, he may be able to do so but not to the same extent as kakashi’s.
Both of them can however predict the movements of their opponents and react accordingly. So both of them are equally proficient with the sharingan but seeing kakashi’s proficiency with just one sharingan and greater experience than itachi, kakashi may have an edge over itachi.
Kakashi received both mangekyo sharingan from obito after obito died. He was already proficient with his left eye and could use the kamui effectively to warp away any targets at a distance and can even warp himself as well, and he even surprised obito with his kamui abilities. After gaining the other mangekyo sharingan, he also received the ability of intangibility. And hence he can phase through most attacks easily.
The extent of kakashi’s abilities were shown after he materialized the susanoo and stabilized it to its perfect form just like madara and sasuke’s. Itachi was never shown to be able to this.
With his susanoo, he could use the kamui shuriken, that warps away any target which it hits. He was able to surprise and even harm kaguya with his susanoo and severed her with a kamui lightning blade.
kakashi’s mangekyo sharingan
kakashi using kamui
kakashi’s kamui shuriken
kakashi blitzing kaguya
kakashi passes through kaguya’s attack unharmed
Itachi possess mangekyo sharingan in both his eyes. His mangekyo sharingan allows him to use Amaterasu with his right eye and tsukuyomi with the left. And using both his eyes, he was able to use the susanoo.
With amaterasu, he could produce black flames which couldn’t be extinguished by any water style jutsu, and could burn fire itself.
In tsukuyomi, he was able to trap his opponent into a genjutsu world and can torture him. For the victim, it would appear as if it has been days whereas actually only few seconds would have passed.
His susanoo was very powerful and possessed sword of totsuka which warped away any target it hit into its gourd and kept them in an infinite genjutsu. His susanoo also possessed the yata mirror. Its a shield capable of blocking all 5 nature transformations. Because of this, itachi was said to be invincible by white zetsu. He was able to warp orochimaru and nagato using his sword of totsuka. He could also use yasaka magatama, his most powerful long range ninjutsu using his susanoo.
itachi’s mangekyo sharingan
itachi using amaterasu(black flames) against sasuke
Itachi using yasaka magatama
So in the end, Itachi is a very strong ninja, no doubt about that. But if kakashi gets both the sharingan, then both of them would be on par with each other but kakashi will have an upper hand. He can counter most of what itachi would throw at him. For amaterasu, he can warp away the flames or even phase through them. His susanoo is in perfect form whereas itachi’s isn’t. He can counter itachi’s yasaka magatama using kamui shuriken. And if itachi tries to use totsuka blade them kakashi would simply phase through it. So kakashi has the upper hand but still both ninja would give each other a tough time and it would be an amazing fight. But for me, Kakashi will win!