Naruto could gain a new form of chakra manipulation. Since Bane was a master of planning and strategy, Naruto might develop a way to use his chakra in a more calculated and devious manner, perhaps creating illusions that are more difficult to detect or traps using his chakra.
He might gain enhanced physical strength like Bane. Bane was known for his brute force, so Naruto could have a similar boost, being able to overpower his opponents more easily in hand - to - hand combat.
He could gain super strength, allowing him to overpower enemies more easily than before. His speed would be enhanced to a level that might make him almost impossible to catch. And he could have the power of hypnosis, which would be useful in combat and getting information from foes.
He might gain a more powerful form of Rasengan, like a Rasengan that can change its shape and properties according to the situation. Maybe he has better control over his Nine - Tails chakra and can use it in more creative ways without losing control.
Another possible power is the ability to control all the elements with extreme proficiency, not just the ones he already has in the original series. He could combine them in ways never seen before, creating powerful and unique jutsus that could defeat any opponent.
Naruto would gain super strength. He could lift extremely heavy objects with ease, like mountains or large buildings in the Naruto world. He would also have super speed, enabling him to move faster than any ninja technique. And of course, he would be able to fly, which is a completely new ability in the Naruto universe.
He might gain the ability to teleport instantly across the village or even between different regions. This would be very useful for quickly responding to threats or attending important meetings. For instance, if there is an emergency on the outskirts of the village, he can be there in a blink of an eye.
One of the new abilities Naruto would gain is enhanced stealth. Shadow the Hedgehog is known for being able to move quietly and blend into the shadows. Naruto, as Shadow, could use this ability to surprise his enemies. He could lurk in the shadows, waiting for the perfect moment to strike. Additionally, he might gain the power to levitate or glide short distances. This would add another dimension to his movement in battle, allowing him to quickly change his position in the air and attack from unexpected angles. His sensory abilities might also be enhanced, being able to detect the presence of enemies from a greater distance, much like how Shadow can sense threats in his own world.
Naruto would gain Frieza's power of flight. This would be a new addition to his skill set. Also, his regenerative abilities could be enhanced similar to Frieza's. If he gets injured in battle, he would be able to quickly heal himself. His new form might also give him the ability to survive in harsh environments, like the vacuum of space which Frieza can do.
Naruto could also develop a zanpakuto - like weapon. Since he is known for his summoning jutsu, his zanpakuto could have the ability to summon different Espada - themed creatures. These creatures could assist him in battle, much like how his shadow clones help him currently.
Naruto would gain some really cool (pun intended) new abilities. The ice - making ability would be the most prominent. He could form ice clones, similar to his shadow clones but with the added advantage of being made of ice and potentially having more durability. His sensory abilities might also be enhanced, as Esdeath has a good sense of her surroundings when using her powers. He could detect enemies hidden in the ice or snow. And, like I said before, the time - freezing power. This would allow him to analyze his opponents' moves during the frozen time and come up with the perfect counter - attack. It would add a whole new dimension to his combat skills.
In this type of fanfiction, Naruto could potentially gain the power to control water more proficiently as Uzushiogakure was known for its water - based jutsu. Maybe he'd also gain some unique sealing techniques that were passed down in Uzushiogakure.