There might be a half - blood or muggle - born wizard who has been hiding their magical abilities due to fear. Harry stumbles upon them and they become friends. Together, they face the challenges of being different in the wizarding world, with Harry sharing his own experiences of being an orphan and dealing with the Dark Lord.
Maybe a house - elf who has broken free from the traditional servitude mindset. This house - elf has developed their own magic in a different way and befriends Harry. They teach Harry about the hidden magic that house - elves possess, which is not taught in regular Hogwarts classes.
Perhaps Harry discovers a group of magical creatures that can communicate with him in a special way. These new friends introduce him to a whole new side of the magical world that he was previously unaware of. For example, they might show him hidden places where rare magical plants grow that can be used for powerful potions.
He could become friends with Jimmy Olsen. Jimmy is always curious and open - minded, so he would be likely to be interested in Harry's magical world. Harry could show Jimmy some simple magic tricks, and they could bond over their shared sense of adventure.
It could be an uncle. Maybe an uncle who was in hiding all this time because he was afraid of Voldemort. Now that Voldemort is gone, he comes out and reveals himself to Harry. He could have a lot of knowledge about the Potter family secrets and magic that he shares with Harry.
Definitely Dumbledore, if he were still alive. He was always a guiding figure for Harry. He could use his wisdom and influence in the wizarding world to ensure that Harry gets the justice he deserves. Also, Neville could be an ally. Neville has grown into a strong and brave character, and he would stand by Harry, offering his loyalty and friendship during this difficult time.
One possible person could be Hermione Granger. She is Harry's best friend and has always been by his side, using her intelligence and magic skills to help him out of difficult situations, which is a form of protection.
A sea turtle that has seen many centuries pass could befriend Melody. The sea turtle could tell her stories about the ancient times of the ocean, give her advice on how to handle difficult situations, and guide her through some of the more dangerous areas of the ocean that are filled with magic and mystery.
Another possibility is a former enemy who has had a change of heart. They could see Naruto's ability to forgive and his strong will, and decide to become his teacher to atone for their past wrongs. This would be an interesting twist in the fanfiction as Naruto would have to learn from someone who was once his foe.
His friends might be shocked too. They could be supportive of Harry, trying to help him come to terms with this new information. For example, Hermione would probably start researching if there was any way to change this in the magical world's past, while Ron would be more about just being there for Harry, sharing his feelings.
He could make friends with a wizard from Australia who has a special ability to communicate with animals native to the Outback.
There's a chance that Naruto's new sensei could be a self - taught ninja who has developed their own unorthodox style. This person sees Naruto's ability to think outside the box and wants to refine that in him. They could introduce Naruto to a new way of looking at chakra control and combat strategies that are completely different from what he has been taught so far.