Yes, there are likely some fanfiction stories out there that involve such a scenario. Fanfiction writers often explore different relationships and interactions between characters from various franchises. However, it's important to note that these are non - canon works created by fans for fans, and they can vary greatly in quality and content.
One challenge could be Luke's pre - existing ideas. He has already started his Jedi training with Obi - Wan and Yoda. So, he might be resistant to some of Ahsoka's new teachings. Another challenge could be Ahsoka herself. She has her own emotional baggage from her past, which might interfere with her ability to train Luke effectively.
Ahsoka's training could greatly enhance Luke's skills. She has her own unique combat and Force knowledge. For example, her experience with different forms of lightsaber combat can be passed on to Luke. This may help Luke become more versatile in battles and also deepen his understanding of the Jedi ways.
There are several. For example, 'Luke, Ahsoka and the Lost Artifact'. In this fanfiction, they embark on a journey to find a powerful and ancient Jedi artifact. It has a great plot with lots of action and character development. Also, 'Ahsoka's Influence on Luke' is quite good. It shows how Ahsoka's wisdom and experience shape Luke's understanding of the Force in a unique way. Then there is 'Luke and Ahsoka: Galactic Guardians' where they protect the galaxy from a dark force together.
One common theme is the passing of Jedi knowledge. Since Ahsoka has more experience and Luke is eager to learn, a lot of fanfictions explore how she imparts her wisdom about the Force, lightsaber combat, etc. to him. Another theme is their combined strength against a common enemy. They are both powerful Jedi, so it makes sense for them to team up against threats in many stories.
One idea could be that Ahsoka tells them stories about their father, Anakin Skywalker. She could share the good times she had with him, like their adventures together. This would give Luke and Leia a more personal connection to their father before they fully understand their heritage.
You can try some popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions on various topics, including Luke and Ahsoka. Just use the search function there and you'll likely find many interesting stories.
Some Discord servers focused on Star Wars fandom could be a great source. Members often share their own fanfics or recommend ones they've read. You might need to search for servers that allow fanfic sharing and discussion. Just be sure to follow the server rules when looking for Ahsoka and Luke fanfics.