One common theme is redemption. Zuko's journey of redemption is a big part of the show, and fanfics often expand on it, sometimes in relation to his sister Azula. For example, some fanfics explore how he tries to help Azula find her own path to redemption.
Another option is Reddit. There are subreddits dedicated to Avatar fanfiction. You can ask the community for their favorite Zuko and Azula fanfics, and they'll likely be more than happy to share some great reads. There are often discussions about different interpretations of the characters in fanfics as well.
A lesser - known but really interesting fanfic is 'Azula in the Spirit World'. Here, Azula gets lost in the spirit world and has to find her way back. During her journey, she encounters different spirits that force her to confront her own spirit and the darkness within her. It's a very unique take on her character and offers a lot of depth to her already complex personality.
One great 'Avatar Azula fanfic' is 'The Redemption of Azula'. It shows a different side of Azula, exploring her possible path to redemption. It has really interesting character development and a great plot that keeps you hooked.
I really like 'Azula in the Spirit World'. This fanfic takes Azula on an adventure in the Spirit World, which is a really cool concept. It shows her interacting with different spirits and how that changes her perspective. There are also some really well - written fight scenes. 'Azula's Allies' is also good. It focuses on Azula forming new alliances and how that affects her relationships with the other characters in the Avatar universe.
I'm not sure specifically about 'zuko azula lemon fanfic' as 'lemon' often implies inappropriate or adult - themed content in fanfiction. However, there are many great Zuko and Azula fanfics that focus on their complex relationship, character development, and the Avatar universe's storylines without such inappropriate elements.
One great 'Zuko x Azula fanfic' is 'The Redemption of Siblinghood'. It delves deep into their complex relationship, exploring how they could potentially heal the rifts between them. The story has a slow - burn element which makes their journey towards understanding each other very engaging.
One great 'Avatar Zuko Fanfic' is 'The Phoenix and the Dragon'. It delves deep into Zuko's journey of self - discovery after the end of the war. The story shows his struggles with his new role as Fire Lord and how he deals with the remnants of his past traumas. It also has some really interesting interactions with the other characters from the Avatar universe, like Aang and Katara, who help him along the way.
Maybe a plot where Mai is kidnapped by enemies of the Fire Nation who want to use her to get to Zuko. Zuko then embarks on a dangerous rescue mission. Along the way, he realizes just how much Mai means to him. Or a story where Zuko and Mai are forced into an arranged marriage by Fire Nation politics. At first, they resist, but as they spend more time together, they start to develop real feelings for each other that go beyond the political arrangement.
Since 'lemon' often refers to more adult - themed content, I cannot promote or discuss such themes. However, in general non - 'lemon' fanfics about Azula and Zuko might often have themes of family reconciliation, as they are siblings in the Avatar universe. There could also be themes of power struggle, redemption, and personal growth for both characters.