One possibility could be that he would bring his magical skills into the world of Westeros. He might use magic secretly to gain an edge in battles, like creating distractions or protecting himself and his allies. For example, he could use a shielding charm during a skirmish with the wildlings.
In such a fanfiction, Harry as Jon Snow would also have to deal with the complex relationships in Westeros. He'd have his loyalty to the Night's Watch, but his newfound magical abilities might make him question the traditional ways. He could start to teach some of his trusted friends or comrades in the Watch a bit of magic, like simple spells for healing or protection. And when it comes to the political intrigue in the Seven Kingdoms, his magical knowledge could be both a boon and a curse. Some would see him as a powerful ally, while others might fear and try to eliminate him.
It could be really strange. Maybe Jon Snow would be revealed to have some hidden connection to the Potter family, like a long - lost relative. He might bring his 'Game of Thrones' - style fighting skills and sense of honor to Hogwarts.
Harry's sense of justice would still be there but might be expressed differently. As Jon Snow, he'd be more likely to take matters into his own hands in a more direct way. For instance, instead of relying on the Ministry of Magic's laws like he did in the wizarding world, he'd be more of a lone wolf in Westeros, making his own decisions on what's right and wrong. He'd also probably be more reserved in showing his emotions, as Jon Snow was not one to wear his heart on his sleeve.
One interesting plot twist could be that fem Harry Potter is mistaken for a long - lost relative of a powerful family in Westeros. This leads to her being dragged into the power struggle. Meanwhile, Jon Snow, who initially distrusts her, realizes she has no interest in power and they end up teaming up against common enemies. It's a great way to mix the two storylines and create unexpected alliances. There are also fanfictions where fem Harry Potter's Patronus has a strange effect on the creatures in Westeros, like taming direwolves in a way that no one has seen before. This causes Jon Snow to view her in a new light and their relationship develops in a whole new direction.
One possible plot could be that as a Lannister, Harry would be thrust into the complex political web of Westeros. He might use his knowledge from his past life to outwit his enemies within the Lannister family, like Cersei or Joffrey if they showed signs of the same kind of tyranny as Voldemort. He could also try to reform the Lannister's reputation which was often marred by their self - serving actions.
Daenerys Targaryen is often paired with Jon Snow in these fanfictions. Their connection in the original series, along with their both being strong leaders, makes for an interesting dynamic. They could rule Westeros together in a new era of peace and prosperity after Jon's rebirth.
One main theme is the clash of different worlds. Harry Potter's magical world and Jon Snow's more medieval, political world are very different. When they meet in fanfiction, it often explores how these differences create both conflict and cooperation.
Perhaps he will discover new powers or abilities in this rebirth. In the 'Dance of Dragons' setting, there could be magic or ancient knowledge that he taps into, which changes the course of the power struggle. For example, he might be able to control dragons, which would be a huge game - changer. He could use this new power to broker peace or topple unjust rulers.
One interesting plot twist could be that Jon Snow is actually a wizard all along but was hidden in Westeros to protect him from Voldemort. In a fanfiction, this could lead to a whole new storyline where he discovers his powers and teams up with Harry Potter to fight against both the Death Eaters and the enemies in Westeros.
One interesting plot could be Harry being reborn as a Stark and using his magical knowledge in the world of Westeros. He could secretly use magic to protect his family from the various threats like the Lannisters or the White Walkers. Maybe he uses a spell to enhance the strength of the Stark soldiers' weapons.
In such a fanfiction, the plot could involve the brother having memories of a past life. This would lead to him guiding Harry in ways that Dumbledore or others couldn't. Maybe they'd explore new areas of the wizarding world that were previously unknown, all while trying to keep their relationship a secret from Voldemort and his followers. Their bond could be a key factor in the ultimate battle between good and evil in the wizarding world.