One possible scenario in a Naruto and Riza Hawkeye fanfiction could be a dimension - hopping adventure. Naruto, with his boundless energy and ninja skills, could end up in the world of Fullmetal Alchemist where Riza Hawkeye resides. Riza, being the skilled sharpshooter she is, might initially be suspicious of Naruto. But as they face common enemies, perhaps some alchemist - turned - villains who are after a powerful chakra - based artifact, they start to work together. Naruto's Rasengan and Riza's precise shooting could make for some amazing battle scenes.
A fanfiction could also focus on a training arc. Naruto could train Riza in chakra control, which she could then use to enhance her shooting accuracy even further. In return, Riza could train Naruto in marksmanship, which could be a useful skill for him in certain situations. This could lead to a friendly competition between them, with both of them constantly trying to outdo each other in their respective skills while also growing as individuals and friends.
One interesting 'naruto hawkeye fanfiction' could be about Hawkeye somehow getting transported to the Naruto universe. He might use his archery skills in a unique way, like against the ninja's jutsu. Maybe he teams up with Naruto and they learn from each other's combat styles.
Another way is to join Naruto or Hawkeye fan communities on social media platforms like Reddit or Discord. Ask the members there if they know of any good 'naruto hawkeye fanfiction'. They might be able to recommend some great stories based on their own reading experiences. Also, some of these communities might even have their own collections or lists of recommended fanfictions.