There is indeed some. However, the quality can vary greatly. Some fanfictions might be really well - written, with in - depth characterizations of both Naruto and Ahsoka, and a believable love story. Others might be a bit more on the cheesy side. It really depends on what you're looking for in this kind of crossover romance.
Yes, there are quite a few out there. You can find some on popular fanfiction websites. Just search for 'Naruto and Ahsoka romance fanfiction' and you'll get a list. Some might focus on how they meet across their different universes and how their relationship develops over time.