A plot twist could be that the bijuu themselves have a collective consciousness that Naruto doesn't expect when he absorbs them. This consciousness could start to influence Naruto's actions during his time travels. For instance, they might guide him towards certain events or people that they believe are important for their own reasons. Maybe they want to correct some past wrongs in the ninja world that were related to their existence. This would add an interesting layer to the story as Naruto has to deal with not only the power of the bijuu but also their will.
It could have a huge impact. With Naruto absorbing all the bijuu through time travel, the power balance among the ninja villages is completely disrupted. Some villages that relied on their own bijuu for protection or status might lose their advantage. This could lead to political unrest as they try to find new ways to assert themselves. Also, the overall perception of power in the ninja world would change. Naruto would become an extremely powerful and perhaps feared figure, which could either inspire others to follow him or try to bring him down.
In fanfiction, if Naruto absorbs all the bijuu, he would likely become an extremely powerful being. His chakra reserves would be off the charts, enabling him to perform incredibly powerful jutsu without much strain. He might also gain new abilities specific to each bijuu, like the ability to control different elements more proficiently or use their unique powers in combat.
Well, if Naruto absorbs all bijuu in this fanfiction, he'd probably be seen as a sort of super - being in the ninja world. His status would change drastically. He might face new challenges too, like dealing with the political unrest that his newfound power could cause. People would either fear him or try to use him for their own gains. And on a more personal level, he'd have to learn to control all that power, which could be a huge struggle, considering the different natures of the bijuu.
In some fanfictions, when Naruto absorbs the bijuu, he might gain overwhelming power. This could lead to him being able to easily defeat powerful enemies that were previously a threat. For example, he could single - handedly take on the Akatsuki without much difficulty.
His character would likely develop a sense of greater responsibility. With all that power from the bijuu, he knows he has to use it for good. He might become more serious and less of the carefree Naruto we know at first. He'd also grow in terms of his self - confidence, knowing he has such incredible strength.
Naruto himself is often a popular character in such fanfictions. Since he has a strong connection with the bijuus, especially Kurama, his time - traveling adventures can create really interesting stories. Another popular character is Sasuke. His power and his complex relationship with Naruto can add depth to time travel plots.
One interesting plot could be the main character traveling back in time and preventing the initial capture of the bijuus. This would completely change the power dynamics in the Naruto world. Another could be a character using time travel to team up with past jinchuriki to fight a new, greater threat.
His power becomes extremely overwhelming. With all nine bijuu, Naruto gains access to an insane amount of chakra. He can perform massive jutsu without much strain. For example, his Rasengan could potentially be magnified to a scale that could destroy large areas with ease. Also, his physical abilities like strength and speed would be enhanced to superhuman levels due to the boost from the bijuu's power.
Well, it could completely change the course of the story. For example, if Naruto travels back in time, he might be able to prevent certain events that led to Kaguya's power becoming so dominant. He could also use his knowledge of future events to train himself or others more effectively, thus altering the power balance in the ninja world much earlier.