Well, in such a fanfiction, Gaara would probably be the center of attention in the Leaf Village, but not always in a positive way. He might be seen as a bit of a nuisance at first. Naruto from Suna would be more of an enigma. He'd have the power of Shukaku within him but be more reserved. Their relationship would develop in a different way. Gaara might be the one trying to reach out to Naruto, instead of the other way around. And the battles they face would also be different, with Naruto having to protect Suna in a more brooding way while Gaara battles for the Leaf Village with his new - found energy.
A 'Naruto and Gaara Roles Reversed' fanfiction could start with Gaara being the one full of energy and constantly getting into trouble in the Leaf Village. He'd be eager to prove himself, much like how Naruto was in the original. Naruto from Suna would have to deal with the harsh treatment from his own village due to being the Jinchuriki. Their first encounter would be really interesting, as their personalities and circumstances are flipped.
The relationship between Sasuke and Naruto (now from Suna) would be different. Sasuke might view Naruto as more of a threat due to his Jinchuriki status. Gaara, in the Leaf Village, would probably be more friendly towards Sasuke, trying to be his friend. Also, the relationship between Naruto and Sakura would be altered. Since Naruto is from Suna, Sakura might be more hesitant or even fearful of him at first.
Well, if they switched roles, Gaara might be the one with the Nine - Tails inside him. He'd have to deal with the villagers' fear and hatred in Konoha. Naruto, on the other hand, would be the Kazekage in Suna. He'd face different political and environmental challenges. For example, Naruto would have to manage the water resources issue in Suna which is quite different from what he's used to in Konoha.
Sasuke, in the reversed role, would develop in terms of his ability to forgive and his patience. He would have to be patient with Naruto's slow progress towards redemption. His character would become more about spreading hope and love in the face of Naruto's negativity. Naruto's development would be a long and arduous process. He would first resist Sasuke's attempts to change him, but as time goes on, he would start to see the error of his ways. His development would be marked by his struggle between his dark past and the new light that Sasuke is trying to show him.
One possible plot could be that Sasuke, in the reversed role, is now the one trying to gain the village's recognition. He might be the underdog with a big dream, like Naruto originally was. He could be using his Sharingan in new ways to protect the village and its people, while Naruto, in Sasuke's role, has a more brooding and solitary nature, perhaps having left the village due to some past event and Sasuke is now on a journey to bring him back.
The relationship would be very different. Instead of Naruto chasing after Sasuke to bring him back, it might be Sasuke trying to reach out to Naruto. Sasuke would be the more empathetic one, constantly trying to break through Naruto's cold exterior.
Well, it could be really interesting. Naruto and Gaara are both complex characters. In such a fanfiction, they might grow up as brothers in a way. They could train together, share their insecurities. Naruto could help Gaara deal with his inner demons earlier, and Gaara could be a more stable support for Naruto when he faces difficulties in the village. Maybe they'd even create new jutsus together.
If the roles were reversed, Sasuke would be the one that Hinata might have a secret crush on. Since he would be the more outgoing and friendly one. And Sasuke would probably be more involved with the village kids, mentoring them like Naruto did. Naruto, as Sasuke, would have a more strained relationship with the Hokage. The Hokage might be constantly worried about Naruto's motives and actions. His relationship with Jiraiya would also change. Jiraiya might be more cautious around Naruto, instead of the carefree mentorship they had in the original story.
A great plot could be that Sasuke, in the reversed role, is the village's hope. He is the one everyone looks up to. Naruto, with a dark past that led him to be bitter, is on a path of self - destruction. Sasuke tries to stop Naruto from causing harm to himself and others. He uses his own positive energy and the power of friendship to make Naruto realize that there is more to life than revenge. This would be a complete role reversal from the original Naruto and Sasuke dynamic.
One interesting concept could be the reversal of the power dynamics. For example, if Naruto was initially a villain or a very shy and introverted character instead of his usual energetic self. It would completely change the story's progression and his relationships with other characters like Sasuke and Sakura.
One idea could be that Sasuke, in the role of the underdog, is constantly trying to prove himself in the village. He might be the one with a big heart, always reaching out to others. Meanwhile, Naruto could be the brooding loner who has a natural talent but is haunted by his past. For example, Sasuke could be the one to develop a new jutsu to protect the village, while Naruto is off on his own journey, slowly coming to terms with his need for connection.