Link would be an outlier in the GoT world. He's used to a more straightforward good - vs - evil dynamic. But in Westeros, he'd have to navigate the complex web of politics. He could probably be a great warrior in the service of a noble house, but his simple and pure-hearted nature might make him a target for the more devious characters. Zelda could be a powerful sorceress, perhaps on par with Melisandre, but with her own goals and a different moral compass.
Kakashi could fit in as a foreign warrior. He could bring his ninja techniques which would seem like magic to the people of Westeros. His stealth and combat skills would make him a valuable asset or a feared opponent in the battles and power plays of the Seven Kingdoms.
Smaug could potentially be a part of the magical elements in the 'Game of Thrones' fanfiction. He could be connected to the old magic that once existed in Westeros. Maybe his presence awakens other dormant magical forces. His actions could also influence the political landscape. For example, if he attacks a certain region, the lords there would have to divert their resources from the power struggles to deal with the dragon threat, which in turn could give an advantage to other houses.
For Sakura, she could be a healer in the Game of Thrones world. With her medical ninjutsu skills, she could treat the wounded from dragon attacks or battles. And she might also learn some of the local magic to enhance her healing abilities, all while having to deal with the political intrigue and power struggles that are so common in the Game of Thrones universe.
She would be a disruptor. Bellatrix's unpredictable and violent nature would immediately set her apart in the Game of Thrones world. She might not play by the political games' rules and just use her dark magic to get what she wants.
The characters from Final Fantasy would bring their unique skills and personalities. For instance, Tidus from Final Fantasy X with his blitzball skills could be like a new form of entertainment in Westeros. His positive and somewhat naive personality might make him an easy target for some of the more cunning characters at first. But his determination and fighting skills would also earn him respect. He could get involved in local disputes and use his skills to help those in need, while also trying to understand the complex power dynamics of the Seven Kingdoms.
Some Naruto characters could fit well. For instance, Sasuke might be like a brooding assassin in the Game of Thrones world, using his Sharingan to his advantage in battles and political intrigue. He could be a lone wolf, similar to Arya Stark in some ways, but with his own unique ninja skills.
Naruto characters could fit in various ways. For instance, Naruto himself could be like a knight errant in the Game of Thrones world. His chakra - based powers would be seen as a strange and powerful form of magic. He might use his Shadow Clone Jutsu to gather information or fight in battles, which would be a very unique ability compared to the normal combat in Westeros.
The Dragonborn could potentially fit into the Game of Thrones universe in several ways. One way is through their dragon - related abilities. In Game of Thrones, dragons are a powerful and rare force. The Dragonborn's natural affinity for dragons could make them a valuable ally or a feared enemy. They could perhaps form alliances with the Targaryens, who also have a strong connection to dragons. Another aspect could be their combat skills. The Dragonborn is often a skilled warrior, and in the brutal world of Game of Thrones, such skills would be highly sought after.
Madara Uchiha is a very powerful and complex character. In a Game of Thrones fanfiction, his skills as a powerful ninja would be quite extraordinary in the Westeros setting. He could potentially be a great warrior or a feared sorcerer - like figure. His Sharingan ability might be seen as some form of dark magic in Westeros. Maybe he would be a lone wolf type of character, not really aligning with any of the existing houses but rather forging his own path in the power struggles, much like he did in the Naruto universe.
The Hulk might be seen as a sort of monster in the context of Game of Thrones. Just like how they have direwolves and dragons, the Hulk could be another mythical - but in this case, suddenly very real - creature. He could be shunned by some and perhaps worshipped as a god by others, depending on how different regions of Westeros react to his existence.