Naruto and Sasuke are two of the most iconic characters in the Boruto series. It wouldn't be a stretch to say that they are the most popular characters that are the face of the entire franchise. Quite a lot of Boruto fans started watching the series because of Naruto and Sasuke, and it wouldn't be a surprise to know that they are left utterly disappointed with the treatment of these two characters.
Boruto: 8 Characters Himawari Uzumaki Will Surpass
Himawari will become one of Boruto's strongest characters. She will surpass these Legendary ninjas.
While the Naruto series established them as legends of the world, the Boruto series has stripped all powers from them. Right now, both Naruto and Sasuke are incapacitated, but eventually they will go on to return. When Naruto and Sasuke do return, fans know that they need to be stronger than before, which would require them to gain new powers.
New Sword (Sasuke Uchiha)
One power-up that has already been confirmed for Sasuke Uchiha after his return in Boruto is a new sword. Fans know that after Sasuke was turned into a tree, his sword was taken over by Boruto Uzumaki. Most recently, this sword was upgraded by Sumire using technology from the future.
This sword is now more dangerous and powerful than ever before. It also possesses the unique ability of always being coated in the user's chakra, which makes it even stronger. On top of that, the sword has a special ability that has not been revealed yet and will most likely be made public knowledge during the climax of the ongoing arc. Sasuke's chakra has already been registered with the sword, and when he does return, he will most certainly regain access to it.
New Prosthetic Hand (Naruto Uzumaki)
As far as Naruto's power-ups go, fans know that one of the most interesting ones that he could gain access to in Boruto upon his return is a new prosthetic hand. Naruto has already tried one prosthetic hand in Boruto, and it allowed him the ability to absorb all forms of ninjutsu. Back then, this hand was only a prototype since it could not expel chakra like Momoshiki's Rinnegan.
However, it could have been upgraded again. After the most recent upgrades, it can be said that this prosthetic hand will most likely be a phenomenal power-up for Naruto Uzumaki that will allow him to fight at the top level once again.
Overall Strength Boost (Naruto Uzumaki)
Naruto Uzumaki would also need an overall strength boost in the Boruto series after he makes his comeback. This is because Sasuke Uchiha has already received his strength boost during the timeskip. It has already been confirmed that Sasuke trained relentlessly during the timeskip before he was sealed. This is exactly why he was able to compete against Code and his Claw Grimes, and even take one of Code's eyes.
Naruto remained sealed during this time, and that is precisely why he would need to catch up upon his return. The series will most likely readjust Naruto's power level, which means that he won't have to undergo training for it.
Wood Release (Naruto Uzumaki)
Naruto Uzumaki has many exciting potential power-ups lined up for him in the Boruto series, provided the author doesn't do him injustice again. One of the most exciting power-ups that Naruto Uzumaki can gain in Boruto upon his return is Wood Release.
It is already known that Naruto possesses the DNA of Hashirama Senju through his prosthetic hand that he received at the end of the Fourth Great Ninja War.
Boruto: 7 Strongest Abilities Of Sasuke Uchiha After Losing The Rinnegan
Sasuke has been nerfed, but he still has many powerful abilities in Boruto.
It is also known that Naruto can manipulate all five Nature Transformations as an adult. As such, it is quite easy to see how Naruto should be able to use Wood Release at will. Given that he has now lost the power of Kurama, Naruto should be able to make use of this ability to give himself an advantage in combat.
Tailed Beast Chakra (Naruto Uzumaki)
While Naruto Uzumaki lost the power of Kurama in Boruto, that doesn't mean that he has to lose the power of other Tailed Beasts as well. Naruto could still seek out the other Tailed Beasts and re-establish a link with them, giving him access to their chakra.
This is quite easy to accomplish, and if he manages to do so, he could then become very powerful once again. In fact, even the loss of Kurama could be mitigated this way, provided Kishimoto doesn't back out.
Rinnegan (Sasuke Uchiha)
Fans know very well that Sasuke Uchiha lost access to the Rinnegan after the battle against Isshiki. However, he still possesses one Eternal Mangekyo Sharingan.
It is possible that, at some point later down the line, this second eye of Sasuke will turn into the Rinnegan via a natural evolutionary process. It is a strong possibility, and if it happens, Sasuke will become even stronger.
Lightning Release Chakra Mode (Sasuke Uchiha)
Sasuke uses many interesting abilities in combat, and one of the most underrated ones that he could be making use of is Lightning Release Chakra Mode. This ability is incredibly powerful and it would give Sasuke an almost impenetrable armor, as well as boost his nerve signals to the absolute maximum.
Sasuke would be faster and stronger than ever before, with hardly anyone being able to keep up with him in combat. Lightning A from Kumogakure made incredible use of this ability, and Sasuke could be the next.