Well, one possibility could be that Naruto is somehow transported to a different realm where Excalibur exists. Maybe he's on a mission and stumbles upon it. He might initially be confused about this strange, powerful sword but then realize its significance. He could then face challenges from those who also want the sword, and his ninja skills would come in handy in protecting Excalibur.
The plot could involve Naruto being in a world where the ninja and Arthurian worlds collide. Excalibur might be the only weapon that can defeat an evil force threatening both worlds. Naruto, with his determination and strong will, sets out to find the sword. Along the way, he meets characters from the Arthurian legend who initially doubt his abilities but are later impressed by his ninja techniques. He has to overcome various trials related to the magic of Excalibur to finally obtain it and save the day.
One possibility is that Naruto is on a mission in a new and strange land. He stumbles upon Vibranium, not knowing what it is at first. He might try to use his chakra on it and discover its unique properties. Maybe he then has to protect it from villains who want to use it for evil purposes.
It could be about a story where elements of the Excalibur legend are combined with the Naruto universe. Maybe it features Naruto characters wielding the Excalibur sword or having adventures related to the power it represents.
One possible plot could be that Naruto stumbles upon the glove during one of his missions in a strange, other - dimensional realm. He might initially be curious about it, not knowing its true power and the evil associated with it. As he investigates, he starts to have strange nightmares similar to those Freddy Krueger induces, and he has to figure out how to stop the glove's influence using his ninja skills and chakra.
Perhaps the plot focuses on the political implications of Naruto having Excalibur. In the Naruto world, the balance of power is important. Naruto already has a certain status, but with Excalibur, it could shift things. Some villages might see him as a threat, while others might seek his protection. This could lead to all kinds of diplomatic issues and battles as Naruto tries to maintain peace while also protecting Excalibur from falling into the wrong hands.
A simple plot could be that Shirou accidentally activates Excalibur's time - traveling ability. He finds himself in Camelot and has to adapt to the new environment. There, he meets King Arthur and other knights, and his knowledge from the future helps him in various challenges while also learning about the true power of Excalibur.
Well, it could be that in a magical crossover world, Harry Potter somehow stumbles upon the fabled Excalibur. Maybe he's on a quest to defeat a new dark wizard who can only be vanquished with Excalibur's power. So, he has to prove himself worthy to pull the sword, just like in the Arthurian legends.
Well, perhaps in the fanfiction, Harry Potter is on a quest outside of the wizarding world and stumbles upon Excalibur. The sword recognizes his pure heart and heroic nature, allowing him to lift it. This event could then draw the attention of both the wizarding and Muggle worlds. Harry would then have to deal with the new responsibilities that come with wielding such a powerful and legendary sword, all while still having to deal with the threat of Voldemort.
The plot could be that Shirou is summoned to the Highschool DxD world by accident. He discovers that his connection to Excalibur is stronger here. He is then forced to participate in the power struggles between the different factions. He uses Excalibur to protect the innocent students in the school from the more aggressive supernatural elements. Along the way, he might fall in love with one of the female characters in the Highschool DxD world, adding a romantic sub - plot to the story.
One possible plot development could be that Naruto discovers the scrolls in an old, abandoned hideout. Maybe the hideout is full of traps set by Sasori long ago. Naruto, with his ninja skills, has to overcome these traps to reach the scrolls.
Well, it could be possible through the concept of alternate universes. In fanfiction, writers often create scenarios where different fictional worlds collide. Maybe Naruto discovers a magic portal that leads him to a world where Excalibur exists. And his ninja skills combined with the power of Excalibur would make for an interesting story.