Uchiha Itachi and Uchiha Shisui are extremely powerful and skilled shinobi in the Naruto series, known for their Sharingan and combat prowess. Determining the outcome of a hypothetical war between them can be subjective, as many different factors and interpretations come into play.
Possesses the Mangekyou Sharingan, which grants him powerful techniques such as Amaterasu (black flames) and Tsukuyomi (magic realm).
Very intelligent and strategic, often relying on his wits to gain an advantage in battles.
Has demonstrated exceptional skills in magic and is a master of deception and manipulation. Suffering from an incurable illness and some degree of physical limitation at the end of life.
Also possesses the Mangekyou Sharingan, with its unique technique, Kotoamatsukami, allowing it to manipulate others without them realizing it.
Considered one of the most skilled members of the Uchiha and known as the “Shisui of the Flicker Body” due to his incredible speed.
Respected and trusted by many, his reputation as a peaceful and wise ninja contributed to his strength.
Given these characteristics, the outcome of the battle between Itachi and Shisui will depend on a number of factors, including their mindset, strategy, and battle conditions. Both possess terrifying abilities that are capable of opposing each other. It is important to note that the Naruto series often emphasizes the importance of emotions, personal relationships, and circumstances in determining the outcome of battles. Therefore, it is difficult to give a definitive answer to this hypothetical scenario and fans may have different opinions on who will win.