Yes, there might be. There are many fanfic communities where fans create crossovers like this. You can start by checking popular fanfic websites such as Archive of Our Own (AO3).
One common theme is the exploration of gender roles. When Noctis is female, it allows for a different take on how she interacts with the male - dominated world of the game. For example, how she might face different challenges or be treated differently in a chauvinistic society within the story's universe.
One great 'Noctis x Reader' fanfiction is 'A Royal Encounter'. It beautifully depicts the relationship between Noctis and the reader in a fantasy setting. The story focuses on how the reader, an ordinary person, gets involved with Noctis in his journey. Another interesting one is 'Noctis' Secret Admirer' which has a lot of cute and heart - warming moments between the two characters.
The appeal lies in the unique dynamic between Ignis and Noctis. Their different personalities - Ignis being more reserved and intelligent, Noctis being the prince with his own charm - create an interesting contrast. In lemon fanfiction, this contrast can be exploited to create engaging stories of love and passion.
Well, Ignis x Noctis lemon fanfiction can be quite interesting. They are two beloved characters, and in these fanfictions, the authors often take creative liberties. The 'lemon' aspect might imply some more mature or sensual content, but it doesn't have to be all about that. It could also be about their unspoken feelings, the glances they share, and how they gradually fall in love. For example, a story could start with Ignis always being by Noctis' side, protecting him, and over time, Noctis realizes his true feelings for Ignis, leading to a beautiful and complex relationship.
A common theme is his physical vulnerability. Since Noctis is often in dangerous situations in the game, fanfics may expand on that, like him getting seriously wounded in a fight with a powerful enemy. Another theme is emotional hurt, such as his feelings of isolation as he bears the heavy burden of his destiny.
Well, when writing a 'Noctis x Reader' fanfic, you should think about the pacing. Don't rush the relationship. Let it develop gradually over the course of the story. For the setting, you can choose a place that hasn't been explored much in the original lore. In terms of the characters, make the reader relatable. Maybe they have a normal job but get thrown into Noctis' extraordinary world. And always keep in mind the themes of the original story, like loyalty and friendship, as they can enhance the relationship between Noctis and the reader.
There could be a Noctis OC fanfiction where the OC is a skilled assassin who initially has a contract on Noctis but then ends up becoming his ally. This OC might have a tragic backstory that led them to the life of an assassin, and through their interactions with Noctis, they learn about loyalty and friendship and start to fight for a greater cause rather than just for money.
Another theme could be his relationships. His friendship with his comrades like Gladiolus, Prompto, and Ignis. When he gets hurt, it can be used to show how they react and support him. It might also involve his relationship with Luna, and how his pain affects their connection. Maybe in a fanfiction, his being hurt could be a barrier to their relationship that they need to overcome.