Another plot could involve the Death Eaters trying to take over Westeros. Voldemort sees the chaos in the Seven Kingdoms as an opportunity to expand his power. The characters from Game of Thrones have to learn about magic quickly to defend their lands against the dark wizards. For example, Jon Snow could be one of the first to realize the potential of magic and try to form an alliance with the wizards from Hogwarts.
Another plot could involve a White Walker invasion in Skyrim. The Night King could lead his army through a magical portal that connects the two worlds. The people of Skyrim, including the various guilds, would have to team up with the houses of Westeros to fight this common enemy. The mages of Skyrim could share their knowledge of magic with the Red Priests and vice versa.
In 'Game of Thrones Crossover Fanfiction', a cool concept would be crossing it with 'Alice in Wonderland'. Alice could wander into Westeros and disrupt the power balance with her strange and magical ways. Another idea is to cross it with 'The Hunger Games'. Have the districts be like the different regions of Westeros and the Capitol be King's Landing. And a crossover with 'Supernatural' where the Winchester brothers hunt down the supernatural threats in Westeros.
Well, for a 'a game of thrones crossover fanfiction', a crossover with 'Star Wars' would be cool. Picture the Nights Watch using lightsabers to fight the White Walkers. Or a crossover with 'The Matrix'. What if characters from Game of Thrones were trapped in the Matrix? Also, a crossover with 'Sherlock Holmes'. The detective skills of Sherlock could be used to solve the mysteries in Westeros.
One plot idea could be Fem Harry being a powerful sorceress in the Game of Thrones world. She could use her magic to influence the political landscape, perhaps helping a particular house gain an advantage. Another idea is that she gets caught in the middle of the battle for the Iron Throne, using her unique skills from the Harry Potter universe to survive and make her mark. For example, her knowledge of potions could be translated into creating powerful elixirs in the Game of Thrones setting.
A cool plot could be the Sith Lords infiltrating the Seven Kingdoms. They could use their dark powers to manipulate the various lords and ladies, causing chaos and power struggles. Maybe they would try to turn some of the noble houses against each other. And on the other side, characters like Jon Snow could potentially be trained in the ways of the Force, becoming a powerful force user in the world of Westeros. This would completely change the power dynamics in the Game of Thrones universe.
Some interesting fanfic ideas could involve the wizards from 'Harry Potter' trying to prevent the events of 'Game of Thrones' from happening. Maybe they see the future of Westeros through some form of divination and decide to interfere. Another idea is a character from 'Game of Thrones' somehow traveling to Hogwarts and learning magic, then bringing that knowledge back to Westeros to change the power dynamics. And a fanfic could explore what would happen if the Deathly Hallows were in the 'Game of Thrones' world. Would they be coveted by the various lords and queens? How would the power of the Elder Wand, Resurrection Stone and Invisibility Cloak affect the already complex world of Westeros?
One idea could be exploring what would happen if a minor character like Gendry had been secretly trained in magic. He could use his newfound powers to unite the smallfolk against the warring nobles. Another plot could revolve around a female knight from the North who disguises herself as a man to fight in the wars, and along the way, she discovers secrets about the White Walkers that no one else knows. Or perhaps a fanfiction where Daenerys and Sansa form an alliance much earlier and together they reshape the power dynamics of Westeros.
In a Halo - Game of Thrones crossover fanfiction, the Forerunners' technology could be a huge factor. What if some of the Forerunner artifacts ended up in Westeros? Different houses might try to claim them, thinking they hold great power. The characters in Game of Thrones would be in awe of the advanced technology, and there could be a race to unlock the secrets of these artifacts, all while the political drama and power plays of Westeros continue.
One idea could be a scenario where the Vikings' raiding parties encounter the Night's Watch from Game of Thrones. Maybe they initially see each other as threats, but then realize they could be useful allies against the White Walkers. Another could be a story about a character from Vikings, like Ragnar Lothbrok, being magically transported to Westeros and having to navigate the complex politics there, similar to how he did in his own land.
One idea could be a character from 'Dishonored' getting transported to the world of 'Game of Thrones'. Maybe Corvo could use his powers to navigate the dangerous political landscape of Westeros. He could use his blink ability to quickly move through the Red Keep, unseen by guards, and gather information that could change the balance of power among the houses.