A really interesting plot for 'Game of Thrones and Shadow of War fanfiction' would be if the Nemesis system from 'Shadow of War' was applied to 'Game of Thrones'. Imagine if every time a character in 'Game of Thrones' wronged another, that wronged character became stronger and more vengeful like the orc captains in 'Shadow of War'. So, for instance, if Cersei wrongs Tyrion too much, Tyrion could become a super - intelligent and powerful 'Nemesis' figure, plotting his revenge in a much more complex and dangerous way than in the original series. This would add a whole new layer of drama and power - play to the 'Game of Thrones' world.
One idea could be a story where the Starks form an unexpected alliance with the Greyjoys to take on the Lannisters. They could use the Iron Islands' naval power and the Stark's knowledge of the North's terrain to launch surprise attacks.
A really cool 'Game of Thrones fanfiction' plot could involve the resurrection of some of the dead characters in a different way. For example, what if Ned Stark was brought back not as a vengeful wraith but as a wise advisor to a new king or queen? His honor and wisdom could shape the future of Westeros in a completely new direction. And it would be interesting to see how the other characters react to his return.
Perhaps a fanfiction where Daenerys Targaryen lands in Westeros earlier and forms an alliance with the Starks before the events of the main series. This would completely shift the political landscape and the fight for the Iron Throne. She could bring her dragons to help fight the White Walkers from the start.
One idea could be exploring what would happen if a minor character, like Gendry, had a more central role in the fight against the White Walkers. He could lead a group of common folk and prove that the power doesn't always lie with the nobles.
Another plot could focus on an orc's rise to power within the Uruk - hai hierarchy. This orc could be different from the others, having unique skills or a different way of thinking. He has to outwit his rivals, make strategic alliances, and deal with the power - hungry captains who don't want to see him succeed.
One idea could be exploring an alternate timeline where the main characters have different allegiances. For example, Sasuke could side with Orochimaru permanently and Naruto has to find a way to bring him back without fighting. Another could be a story where the Akatsuki are actually working for a greater good that was misinterpreted, and Naruto teams up with them to fight a common enemy.
You could write a fanfiction where Talion travels to different regions not explored in the game. He might encounter new cultures and races, some friendly and some hostile. This could lead to him having to adapt his combat and survival skills. And perhaps he discovers a long - lost artifact that has the power to either greatly enhance his abilities or put him in a dangerous position as others seek to take it from him.
A great plot for Shadow the Hedgehog game fanfiction could involve Shadow's relationship with other characters. For instance, a story about how he forms an unlikely friendship with a young and naive creature in the Sonic world. He then has to protect this new friend from the chaos and danger that constantly lurks in their world. This would show a different side of Shadow, his more protective and caring side.
One idea could be reincarnating as a minor character, like a servant in King's Landing. You could use your modern knowledge to avoid the chaos of the city and slowly rise in power by befriending key players. Maybe you know of some herbal remedies that could save a noble from a deadly illness and gain their favor.
One interesting plot idea could be a character who was thought to be dead actually surviving and secretly plotting revenge. For example, a minor character who was presumed killed in a battle but managed to escape and now is working with an unexpected ally to change the power dynamics in Westeros.