One common theme is adventure. Given their roles in the Star Wars universe, many fanfictions will have them going on exciting quests together, facing off against the Empire or other threats.
The exploration of their relationship is also quite common. It could be a platonic partnership where they learn from each other and grow as Jedi. Or, in some cases, it might be a romantic relationship that develops over time as they share their experiences and emotions. Some stories also focus on how they cope with their past traumas and how their relationship helps them heal.
A theme that often appears is the idea of a forbidden love. Given their different positions and the situation in the Star Wars universe, their love is sometimes portrayed as something that goes against the norm. For example, in some stories, they have to hide their feelings from others.
Many 'ahsoka x reader fanfiction' have the theme of discovery. The reader discovers new aspects of the Star Wars world, new powers, or new secrets along with Ahsoka. There is also the theme of trust. Given the dangerous situations they get into, the reader and Ahsoka have to learn to trust each other completely, and this is often a central part of the story.
Redemption is also a theme. Since Barriss made some controversial choices, some fanfictions might have Ahsoka helping Barriss find her way back, either morally or in terms of her place in the Star Wars universe.
One common theme is adventure. They often go on exciting quests together, which deepens their bond. For example, in many fanfics, they explore uncharted regions of the galaxy.
One common theme is mentorship. Hera often acts as a mentor to Ezra, guiding him in his Jedi training and in making decisions. For example, in many fanfictions, she helps him control his emotions when using the Force.
A frequent theme is friendship or camaraderie. Since they are both heroic characters in their respective stories, they are often depicted as forming a strong bond. This could involve them helping each other out of difficult situations. Also, the theme of discovery is common. They discover new things about each other's worlds and abilities, which can lead to character growth for both Harry and Ahsoka in the fanfiction.
One common theme is loyalty. Their loyalty to each other, whether as master - apprentice or as friends, is often explored. Another is growth. How they both grow as individuals through their relationship with each other.
One common theme is adventure. Given Ahsoka's nature and the potential of the Oc Droid X, they might embark on various quests together. Another theme could be friendship or even a mentor - mentee relationship, where Ahsoka helps the Oc Droid X to understand things better, like the ways of the Force or the galaxy at large.
One appropriate topic could be their training together. They are both powerful in their own ways, and a fanfiction about them sharing combat techniques or learning from each other would be great.
One appropriate topic could be their joint adventures in the galaxy. They could team up to fight against a new and powerful enemy, using their unique skills and powers to protect the galaxy.