One great 'Hermione and Luna Fanfic' is 'The Bond of Brilliance'. It beautifully explores their friendship. The story shows how their different personalities complement each other. Hermione's practicality and Luna's dreamy nature create an interesting dynamic.
A good 'Hermione and Luna Fanfic' often focuses on their unique relationship. Since Hermione is logical and Luna is more of a free - spirit, exploring how they interact and understand each other is key.
There could be some out there. However, it's important to note that in the world of fanfiction, the availability and popularity of such stories depend on the size and activity of the Harry Potter fanfic community interested in this particular pairing. Some smaller, more niche fanfic groups might have some great works that are not as widely known as those in more mainstream pairings.
In these fanfictions, they often interact with great respect for each other. Hermione, with her logical mind, might initially be a bit skeptical of Luna's more out - there ideas, but she soon comes to appreciate them. Luna, on the other hand, admires Hermione's intelligence and determination. They might exchange ideas about magic, with Luna sharing her more esoteric knowledge and Hermione providing the more textbook - based facts.
A plot could revolve around a school project where they team up. They decide to study a rare magical phenomenon that has been causing strange things to happen at Hogwarts. As they dig deeper, they realize it's related to a forgotten spell from the past. They face opposition from some students who think they're meddling in dangerous magic, but they persevere and eventually solve the mystery.
One great 'Hermione and Luna Fanfiction' is 'The Unlikely Bond'. It beautifully portrays their friendship and how they support each other through the challenges at Hogwarts. The story delves into their different personalities, Hermione's studiousness and Luna's dreamy nature, and shows how they complement each other.
One possibility in this fanfiction could be that Hermione is a demigod of Athena, given her intelligence and wisdom. She could use her godly gifts to solve complex magical problems. Luna, perhaps, could be a demigod related to a more ethereal deity, like Artemis. Her connection to the moon and her dreamy nature might be enhanced by such a heritage. They could go on adventures together, using their combined powers to face magical threats that normal wizards couldn't handle.
In a story, Hermione's character could grow by facing a magical problem that her books can't solve immediately. This would force her to think on her feet and trust her instincts more. Ginny could be developed by having her deal with the pressure of being a role model for younger students. Luna, on the other hand, could be shown as becoming more assertive in her beliefs and not just being the dreamy girl, but someone who actively stands up for what she believes in, even if it goes against the norm at Hogwarts.
Well, first of all, as mentioned before, AO3 is an excellent resource. You can also try looking on Tumblr. There are often fanfic recs (recommendations) on Tumblr blogs dedicated to Harry Potter fanfiction. Additionally, some Harry Potter - themed Discord servers might have channels where people discuss and share their favorite fanfics, including those about Hermione and Luna in a lesbian relationship.
One great fanfic could be one where they team up for a magical mystery adventure in Hogwarts. They might be trying to solve a series of strange happenings that the teachers can't figure out. Hermione's intelligence, Luna's unique perspective, and Ginny's courage would make for an exciting story.