Hermione is known for her academic approach to magic, so she might have a more refined and precise control over spells she has studied. Percy, on the other hand, could have a more instinctive magic related to leadership and order. Maybe he can magically organize things or people with ease.
Since they are twins in this fanfiction, they could have equal potential in different areas. Hermione's magical ability might shine in the classroom and in research, while Percy's could be more prominent in practical situations outside of school. But they could also learn from each other and develop new magical skills together. For instance, Percy could teach Hermione some of the practical magic he has learned from his experiences in the Ministry, and she could introduce him to new spells from her extensive reading.
Since Hermione is highly skilled in academic magic, she could use her knowledge to analyze Merlin's magic. Maybe she discovers ways to enhance his spells or make them more efficient. Merlin, with his natural and powerful magic, could help Hermione break free from some of the limitations of the Hogwarts magic system. For example, he might show her how to draw magic from sources other than a wand, which could be a game - changer for her.
They would likely raise them with a strong sense of honor and courage. Percy would teach them about the power of the sea and how to use it for good. Annabeth would instill in them a love for knowledge and strategy. They would also train their twins in combat skills to protect themselves in the dangerous world of demigods.
They could develop a shared form of telepathy. Since they're twins, it's not far - fetched to think they could communicate without words. Maybe they could combine their magic to create a new kind of protective shield that's stronger than any single spell. Another ability could be the ability to sense each other's emotions more acutely, which could then be harnessed to boost their magic when they're in danger or facing a difficult task.
In the past, Tom's magical abilities were already quite strong even as a young student. His natural talent for magic was evident. However, if Harry travels back in time, he would bring with him the knowledge and skills he has learned in his own time. So in terms of spellcasting knowledge, Harry might have an edge as he knows spells that were not yet invented or commonly known in Tom's time. But Tom's raw power and his understanding of magic from his own era's perspective would be formidable.
Arthur's main ability is his leadership and his connection to the sword Excalibur which gives him great power in battle. He is also a skilled warrior trained in the ways of medieval combat. In contrast, Percy has his demigod powers. He can control water, which is a very powerful ability especially in combat situations near large bodies of water. He also has the enhanced strength and speed typical of a demigod.
If Percy and Thalia were twins, their relationship with Luke would change significantly. Luke might see them as a bigger threat to his plans. He might try to drive a wedge between them, knowing how strong they could be together. Their relationship with Chiron would also be different. Chiron would have to train them in a way that takes advantage of their twin connection, perhaps teaching them special combat moves that only work when they work in tandem. The gods would also treat them differently. They might be more watchful of the twins, fearing their combined power could disrupt the balance among the demigods.
As twins, they would have a special connection. They could start to have a sort of unspoken understanding. For example, when one of them is in danger, the other could sense it. Their relationship would be a mix of brotherly love, friendly competition, and mutual respect. They would grow together, both in their magical abilities and in their understanding of the wizarding world and their place in it.
Harry and Ron would probably be shocked at first. Ron, especially, might have a hard time accepting it because of his past relationship with Hermione. But eventually, they would come around because they care about Hermione. Ginny would likely be more open - minded and try to be supportive. Other friends from Hogwarts might also be divided, some might be against it because of the long - standing rivalry between the Gryffindors and Slytherins, while others would see it as a chance for unity in the wizarding world.
Superman's strength, flight, and heat vision are very powerful. In comparison, characters like Captain America in the Marvel universe have more of a combat and leadership skill set rather than superhuman physical abilities. However, Thor also has super strength and the ability to control lightning, which could be on a similar level to Superman's powers in some ways.
Naruto has his chakra-based abilities like Rasengan and shadow clones. Frieza has his powerful energy blasts. Naruto's clones could be used to confuse Frieza while he tries to get in close for a Rasengan strike. Frieza's energy blasts are long - range and very destructive. However, Naruto's speed and agility in combat might give him an edge in dodging those blasts.