Boruto fans are treated with a surprise with the display of Sarada Uchiha's Mangekyo Sharingan, as she fights the Shinju clone Ryu. However, it comes with the fact that she is struggling to use it because of her lack of chakra. Fans have come up with the idea that she could develop a Byakugo to store chakra and use her dojutsu a lot easier. It is something that her mother, Sakura Haruno, can help with.
Viewers of the original series know that Sakura has mastery of the Byakugo, which she learned from Tsunade, and she could return to relevancy in Boruto by teaching this to her daughter. On the other hand, there is a chance that she's already taught Sarada during the time skip and it is going to become a plot point in the coming chapters or a bit further down the line.
Disclaimer: This article is a speculative theory and reflects the writer's opinion.
Explaining why Sakura giving Sarada a Byakugo in Boruto could fix the latter's Mangekyo Sharingan problem

As she manages to defeat Ryu with her Mangekyo Sharingan, Sarada Uchiha gets weakened because of her lack of chakra. This moment has led to many fans suggesting that her mother, Sakura Haruno, could teach her the Byakugo. This would allow her daughter to store a significant amount of chakra and use her jutsus in a much stronger manner.
It goes without saying that Sarada's father, Sasuke Uchiha, has been a prevalent figure for her character during the Two Blue Vortex portion of the series. Therefore, having Sakura involved with her Mangekyo Sharingan problems could be a logical way for her to contribute to the story and there is an argument to be made that this already happened.
The Studio Pierrot anime adaptation has Sakura telling Sarada to practice her chakra control and the time-skip could see the character go through this training to eventually learn the Byakugo. There is nothing in the manga that could contradict what's established in the anime and would be a fitting progression for the character.
What this could mean for both characters?

A plausible reason to have Sakura helping Sarada with her Mangekyo Sharingan problems is that the latter would return to relevancy in the Boruto series. While Naruto and Sasuke have been taken out of commission for different reasons, she is still alive and capable of contributing to the plot, with this situation being a very good example of how she could help in a logical manner.
Moreover, it would help both characters to share time together in a way that could benefit Sarada in the long run while also maintaining Sasuke's influence through her Uchiha heritage. As mentioned earlier, it might help bridge the two sides of Sarada's character when it comes to her parents and depict how she has the best of both worlds in that regard.
Final thoughts
The narrative could take a logical step by having Sakura teach Sarada how to use the Byakugo and do so in a way that would work in a quite natural manner. It would also give a chance to both characters to spend time together, thus helping the young Uchiha in her development moving forward.
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