In this fanfiction scenario, they would probably be assigned dangerous and complex missions. For example, exploring ancient and cursed ninja sites. Naruto's curiosity and Itachi's knowledge would be useful here. Itachi might know some of the secrets of these places from his clan's history, and Naruto would be brave enough to venture into the unknown. They could also go on missions to stop large - scale terrorist attacks by ninja organizations. Their combined power and different skill sets would be crucial in preventing disasters and protecting the ninja world.
Missions involving diplomatic relations could also be on the table. Naruto has a way of making friends and influencing people, and Itachi's calm and composed presence could add an air of authority. They could be sent to mediate between feuding ninja villages. Another type of mission could be rescuing important hostages. Naruto's determination and Itachi's stealth and combat abilities would make them a great team for this. Itachi could silently take out the guards while Naruto locates and frees the hostages.
Their team dynamic would be quite complex. Naruto is very open - minded and friendly, always eager to make friends. Itachi, having been through so much in his life, is more reserved. Naruto would be excited to have such a powerful teammate like Itachi and would constantly pester him for tips on becoming stronger. Itachi might initially be annoyed by Naruto's boisterousness but would gradually come to respect his determination. In battles, Naruto could use his large chakra reserves and shadow clones to create distractions while Itachi uses his Sharingan to find the enemy's weak points and strike. They could form a formidable team if they could get past their initial differences.
Naruto could be gathering intelligence. Since he can move around freely in many places without arousing too much suspicion, he might be using his friendly and open - natured guise to collect information that Itachi needs. For example, he could be finding out about the movements of other ninja clans or potential enemies of Itachi's plans.
One challenge would be living up to Itachi's expectations. Itachi is a prodigy, and Naruto would have to work hard to match his skills. Another challenge could be dealing with Itachi's secretive nature. Naruto is used to open communication in his team with Kakashi and the others, but Itachi might not be as forthcoming. Also, Naruto might face opposition from other ninja who don't trust Itachi, and being on his team could put Naruto in a difficult position.
They could undertake missions to stop dark magic users. With Zeref's knowledge of dark magic and Naruto's combat skills, they would be well - equipped. For example, if there was a mage using forbidden spells to cause chaos, their guild could be called in to stop it.
He might take on rescue missions. For example, rescuing hostages from bandits or rogue ninjas. Since he has a strong sense of justice, he'd be drawn to such tasks. He could also be hired for protection missions, like guarding a caravan traveling through dangerous lands.
One possible plot could be that they are tasked with protecting a powerful and ancient ninja artifact. Naruto's raw power, Itachi's strategic mind, and Yugao's stealth skills are all needed. Along the way, they face off against other ninja clans who also want the artifact for their own purposes. They have to battle not only the external enemies but also their own internal doubts and differences to succeed.
It would be a wild departure from the original story. Naruto's character would likely have a much more serious and calculating side, influenced by Itachi. His goals might be more in line with Itachi's own motives in the original series.
They could go on adventures to stop powerful demons that threaten the balance of the DxD world. Naruto's combat skills and Rias' leadership would make them a formidable team. They might also travel to different dimensions in search of rare items or knowledge. For instance, they could explore a dimension where there are unique forms of magic that Naruto could learn to combine with his chakra.
Naruto might give Itachi some traditional Konoha food as a gift. Since Itachi has been away from the village for a long time, he might miss the taste of home.
Well, in a fanfiction where Naruto replaces Itachi, the whole power dynamic in the story would shift. Naruto has his own set of powers and abilities like the Nine - Tails chakra. This would change how battles are fought. In Itachi's place, Naruto might be more open about his intentions and not keep so many secrets. He could inspire the Uchiha clan in a different way, perhaps leading them towards a more positive path rather than the path of revenge and secrecy that Itachi's actions led to.