In these fanfictions, the demigods often try to understand the SCPs from their own perspective of good and evil. They might see some SCPs as new kinds of monsters to defeat. On the other hand, some SCPs could be seen as potential allies if they share a common goal. For instance, if there is an SCP that is being hunted by a more dangerous entity, the demigods could form a temporary alliance with it. The interactions are full of tension and discovery as the two different worlds collide.
The Avengers might be protective of baby Percy. They could use their skills to keep him safe from any danger. For example, Captain America could use his combat skills and leadership to organize the protection of Percy.
Annabeth, if she were with Percy, would be more interested in the architecture and strategic planning of Troy. She could offer her knowledge to the Trojans or the Greeks, but they might not trust her either. And Percy would have to protect her from those who might see her as a threat or a sorceress.
Percy would probably be very cautious around Morathi at first. Given his experiences with tricky and powerful beings, he'd be on guard. Morathi, being the conniving character she is, might try to charm Percy or manipulate him. For example, she could use her allure to make Percy lower his defenses, but Percy's loyalty to his friends and his own sense of right and wrong would likely make him resist.
In some fanfictions, their powers might combine in unexpected ways. Maybe when Arya is in a tight spot, Percy's power somehow enhances her speed or strength. Or when Percy is having trouble controlling a large body of water, Arya's mental focus and determination help him gain better control. Their powers interacting can open up a whole new realm of possibilities for exciting and unique storylines.
Hulk and Percy could have an interesting interaction. Hulk's brute strength and Percy's agility and water powers could make for a great dynamic. They might start off by having a little test of strength, but then realize they need to work together. And when it comes to Captain America, he and Percy could bond over their sense of duty and loyalty. Cap would probably respect Percy's commitment to protecting his world, just as Percy would admire Cap's leadership.
The demigods from Percy Jackson's world would interact with the Diablo characters in different ways depending on their personalities. Annabeth, being the strategic thinker, would try to analyze the Diablo characters' weaknesses and form plans. She might try to communicate with any intelligent Diablo creatures to find out more about their world. Grover, with his connection to nature, might be really disturbed by the corrupted and dark nature of the Diablo world. He could try to find any remnants of good or nature in that world to help in the fight against the dark forces. And when it comes to the Diablo characters, some of the more cunning ones might try to manipulate the demigods for their own ends.
The interaction could also be more action - oriented. Suppose they are all in a dangerous situation, like a powerful dark wizard from the Naruto world has somehow entered the world of Percy Jackson and is causing chaos. Naruto would use his combat skills and jutsus, Percy would rely on his demigod powers like controlling water and his swordsmanship, and Hestia could use her divine powers to protect them or provide strategic advice on how to defeat the enemy.
Well, Percy Jackson's interaction with the Mystic Falls characters would be really interesting. He'd see the vampires' abilities as something different but not entirely unfamiliar, given his experience with all sorts of mythical creatures. He could start off by being a bit of an outsider, but as he gets to know them, he'd start to bond. For instance, he might help Bonnie with her magic, sharing his knowledge of the gods' magic. With Caroline, he might be amused by her perky and determined personality. And when it comes to Klaus, Percy would be on high alert, ready to use his powers if Klaus made any wrong moves, but also trying to understand his motives as he's used to dealing with complex and powerful enemies.
Percy would likely be very curious about the characters in the Overlord world. He might approach them with his usual friendly and adventurous attitude. The Overlord characters, depending on their nature, could either be hostile or intrigued. For example, the more powerful and evil - inclined characters might see Percy as a threat and try to eliminate him. But the more neutral or good - hearted ones could be interested in learning about his powers and his world.
Well, Percy's ability to control water and Frozen characters' ice powers could create some cool interactions. For example, Percy could make a stream of water and Elsa could freeze it to create an ice bridge. It would be a great way for them to traverse difficult terrains.