In a Fairy Tail fanfiction with Shirou Emiya, there could be a plot where Shirou's ability to trace and replicate weapons is seen as a very rare and powerful form of magic in the Fairy Tail world. The guild tries to keep his identity a secret to protect him from other guilds who might want to use his power for their own gain. Meanwhile, Shirou is on a quest to understand the origin of his power in this new world. He teams up with Erza to explore ancient magic sites, and along the way, they encounter various challenges that test both their physical and mental strength. As they progress, Shirou starts to develop a new understanding of his own abilities and how they can be used for the greater good in the Fairy Tail universe.
One plot idea could be Shirou Emiya finding himself in the world of Fairy Tail and having to adapt to the magic - based society. He might try to use his Reality Marble in unique ways to combat the dark guilds. Another could be him teaming up with Natsu and his friends to take on a powerful, otherworldly threat that has somehow entered the Fairy Tail universe. He could also learn new forms of magic from the wizards in Fairy Tail, like learning how to incorporate Fairy Tail - style elemental magic into his existing abilities.
One plot idea could be Dark Shirou in a post - apocalyptic world where he uses his skills to survive and rule a small territory. Another could be his journey to find a way to reverse his dark transformation. Or a plot where he has to face his darker self in a psychological battle within his own mind.
Another plot could be that Shirou discovers a new, highly competitive gamer community. He starts from the bottom but his determination and strategic thinking, which he has from his heroic deeds, help him rise through the ranks. He might make new friends and rivals in this community.
Another plot could involve Shirou reincarnated in a modern superhero world. He might struggle to fit in at first, but then realizes his abilities can be used to fight super - villains. His noble phantasm could be adapted in a unique way to combat the new threats in this world.
One idea could be that Archer is transported to an alternate universe where Shirou has a completely different personality. Maybe Shirou is a villain in this world, and Archer has to figure out how to deal with him. Another plot could involve them teaming up to fight a powerful, new enemy that neither could defeat alone. For example, a powerful mage from a different dimension who wants to conquer their world.
One idea could be Shirou using his projection magecraft in the Highschool DxD world to create unique weapons during battles against the devils or fallen angels. For example, he might project Excalibur to fend off a powerful devil attack. Another plot could involve Shirou forming an alliance with Issei and his group, teaching them about his different combat techniques and how to better strategize in fights. He could also have a romantic sub - plot with one of the female characters from Highschool DxD, like Rias, where his noble and self - sacrificing nature attracts her.
One idea could be Shirou finding himself in the Rosario Vampire world and having to adapt to its unique rules. Maybe he uses his skills from his own world to protect the school from various threats that are different from what he's used to.
Shirou Emiya's abilities would have an interesting adaptation in the Fairy Tail universe. His tracing magic could be related to the concept of analyzing and replicating magic in Fairy Tail. He might be able to study the magical auras of different spells and then create his own versions. His Reality Marble, Unlimited Blade Works, could be a very high - level form of spatial magic in the Fairy Tail context. It could be seen as a pocket dimension where he stores all the weapons he can project. In battles, he could use this ability to surprise his opponents. For example, he could suddenly pull out a large number of weapons from his Reality Marble during a fight, much like how some Fairy Tail wizards can summon multiple magical items or creatures. Also, his skills in swordsmanship would be highly valued in a world where melee combat is also an important part of magic battles.
Well, Shirou could form an unlikely alliance with some of the characters in Highschool DxD. Maybe he teams up with Issei and his group. Since Shirou has a strong sense of justice, he could help them in their battles against stronger enemies. He might also teach them some of his combat techniques, like how to better utilize their own powers.
Another plot could involve Shirou getting a glimpse into the past of the Grail War through some sort of magical artifact. He discovers secrets that were long buried and this knowledge could either help him in the war or put him in greater danger as others may want to silence him.
One plot idea could be Shirou Emiya, as an angel, arriving at the Highschool DxD world and getting involved in the ongoing power struggles. He might use his skills from the Fate series to help out the various factions while also trying to maintain his angelic identity.