Sarada does have Mangekyou Sharingan in the manga. This development comes as a significant plot twist and showcases her growth and potential as a character. It occurs after she faces certain challenges and undergoes intense training.
Yes, Sarada awakens Mangekyou Sharingan. The manga builds up to this moment with a series of intense battles and character developments that lead to this power awakening.
One possible plot twist could be that Naruto's new Mangekyou Sharingan gives him the ability to access a new form of Sage Mode. Since the Sharingan has unique powers and Sage Mode is Naruto's own power, their combination might create something unexpected. For example, he could use the Sharingan to better target his Sage chakra, making his attacks more precise and powerful.
There could be a fanfiction where a villain has mastered both the Mangekyou Sharingan and Susanoo in a way that no one has seen before. This forces the heroes to find new ways to combat this powerful foe, perhaps by delving into ancient jutsu that can counteract these abilities. It would be full of intense battles and strategic planning.
There's a really interesting fanfiction that focuses on a female character getting the Mangekyou Sharingan and Susanoo. It's unique because it delves into how a female ninja copes with the power that is usually associated with male Uchiha characters. It shows her struggles, her triumphs, and how she changes the perception of these powers in the Naruto universe.
With Sasuke, their relationship would become more complex. Sasuke might be both jealous and intrigued by Naruto having the Mangekyou Sharingan. Jealous because it was always an Uchiha thing, and intrigued because he wonders how Naruto will use it. This could lead to more intense rivalries and also more opportunities for them to understand each other better.