Given the lack of details, Elaine could be many things in her secret novel. She could be a young girl coming of age, dealing with the challenges of growing up. She might be an older woman looking back on her life and sharing her wisdom through the story. Or she could be a completely fictional creation, a character with unique abilities or a special mission within the world of the novel.
One idea could be to have the characters from 'Throne of Glass' (TOG) and 'A Court of Thorns and Roses' (ACOTAR) meet in a magical realm created by a powerful ancient artifact. For example, Aelin from TOG could be on a quest to find a way to defeat a new, powerful enemy and accidentally stumbles into the world of ACOTAR. There, she meets Feyre and they initially have a bit of a clash due to their different upbringings and leadership styles, but then realize they can work together to solve a problem that threatens both of their worlds.
Miss Elaine could be the author or storyteller of these bedtime stories. She might be a creative person who loves to share magical and inspiring tales with children to help them fall asleep peacefully.
When writing an ACOTAR and TOG crossover fanfic, character development is key. You can't just throw the characters together without considering how they will grow and change in this new situation. For instance, if you pair up Chaol from TOG with Lucien from ACOTAR, think about how their different backgrounds and experiences will influence their relationship. Maybe Chaol's loyalty to his kingdom will be challenged by Lucien's more fluid view of loyalty among the fae. Also, don't be afraid to experiment with the magic systems. Try to find unique ways for the characters to use their combined powers. This will make your fanfic more engaging and original.
Good fanfic writing for a TOG and ACOTAR crossover requires a deep understanding of the source materials. Research the lore, the politics, and the relationships in both series. For the plot, think of something that challenges the characters from both worlds. A good way is to introduce a new, powerful enemy that neither world has faced before. In terms of character development, let the characters grow and change as a result of their interactions. For example, if Rowan from TOG meets Azriel from ACOTAR, they could learn from each other's combat skills and ways of thinking. Also, pay attention to the pacing of your story. Don't rush the important moments and build up the tension gradually.
Perhaps a crossover where the magic systems cross over. The valg from 'tog' could somehow seep into the world of 'acotar' and the characters from 'acotar' have to learn about the valg and how to combat it using the knowledge that Aelin and her crew have from 'tog'. This could lead to some really interesting battles and alliances.
First, re - read both series to get a firm grasp on the characters, their personalities, and the worlds they inhabit. Then, decide on a central plot point that would bring the two worlds together. It could be as simple as a portal opening between the two realms. Next, choose which characters from each series will be your main focus. For example, you might want to start with Feyre and Celaena as they are strong female leads.
I'm sorry, I don't know the specific 'Ban and Elaine love story' without more context. It could be a story between two ordinary people, or perhaps it's from a specific piece of literature, movie or local folklore.
Once upon a time, there was a little girl named Lily. She lived in a small village surrounded by beautiful mountains. One day, while exploring the forest near her home, she found a magical flower. The flower had the power to make people's wishes come true. Lily was very excited. She made a wish to have enough food for her poor family. The next day, her family found a big basket full of delicious fruits and bread at their doorstep. It was a miracle. And Lily learned that kindness and discovery could bring wonderful things.