One possible ability could be enhanced cutting power. It can slice through the toughest of materials, like it's cutting through butter. For example, it could easily cut through solid rock or even chakra - enhanced defenses.
Perhaps it has the ability to absorb chakra. When Naruto is in a fight against an enemy with a large amount of chakra, the sword can suck in some of that chakra, weakening the opponent and strengthening Naruto at the same time.
The sword might have a teleportation - like ability. When Naruto is in a tough spot, he can use the sword to create a portal or something similar. He could quickly escape from danger or surprise his enemies by suddenly appearing behind them using the sword's power.
The sword might also have a connection to the spirit world. It could allow Naruto to communicate with the spirits of the Uzumaki clan or gain insights from their past. This would give him an edge in battles as he could learn from the experiences of his ancestors.
Maybe the dragon sword has the ability to absorb chakra. When Naruto is in a fight, he could use this to his advantage by draining his opponents' chakra through the sword when it makes contact. This would weaken his enemies and at the same time, the absorbed chakra could be used to power up the sword's other abilities.
One possible ability could be enhanced cutting power. It might be able to cut through almost any material, even chakra - based defenses with ease.
In certain fanfictions, Naruto's special eyes are linked to time - related abilities. For example, he might be able to slow down time perception in a fight, which would make it seem like his opponents are moving in slow motion while he can move at normal speed. This would make him nearly unbeatable in combat. Also, these eyes could potentially allow him to see into the past or future, giving him crucial information for various situations, like preventing disasters or learning secret techniques from the past.
The sword might be able to enhance Naruto's existing jutsus. For example, his Rasengan could become more powerful when combined with the sword's energy. It could also give him new elemental powers, like the ability to control lightning or fire in a different way than before.
The sword could have the ability to cut through any chakra - based attacks. Since Naruto's world is full of ninjas using chakra, this would be a very useful ability. It would allow Naruto to easily defend against and counter his opponents' attacks.
The Uzumaki sword might have the power of sealing. The Uzumaki clan was known for their sealing techniques. So, it's possible that the sword can be used to seal away powerful enemies or even seal away dangerous jutsu. It could also have the ability to cut through powerful defenses. Maybe it has some sort of special chakra edge that can break through barriers that are otherwise difficult to penetrate. Additionally, it could have a connection to the Uzumaki's life - force, allowing Naruto to draw on some of that power in times of need.
Since Naruto is known for his shadow clones, their son could have an upgraded version of this ability. He might be able to create clones that not only look like him but also have different skills based on Talia's abilities. For instance, some clones could have her stealth skills while others could have her strategic thinking abilities, making his combat and problem - solving strategies much more diverse.
The demon sword could potentially give Naruto new jutsu. Maybe it has some sort of dark energy that he can learn to manipulate and turn into unique attacks. However, he would have to be careful not to let the dark side of the sword overtake him. He might start with simple things like using the sword to focus his chakra in a different way, creating new types of rasengan-like attacks.
The sword might have special abilities that Naruto can tap into. For instance, it could allow him to use a new type of chakra or jutsu. Maybe it gives him the ability to control shadows or fire in a way he couldn't before. This would completely change his fighting style and make him even more formidable against his enemies.