It could be from a foreign land. Maybe some traveling merchants brought it to the Hidden Leaf Village. They lost it on their journey and Naruto just happened to stumble upon it.
Well, he might put on the suit and suddenly feel a new sense of confidence. Maybe he uses it to infiltrate an enemy hideout. He could pretend to be a rich merchant or something, and use his ninja skills along with this new disguise to gather intel.
One possible fanfiction could be about Kushina finding Naruto in a situation where he's lost in a forest. Maybe she uses her unique chakra sensing abilities to track him down. It could be a heartwarming story of a mother reuniting with her son.
One possible scenario in this fanfiction could be that Naruto discovers an ancient and mysterious shrine in the forest. The shrine might hold some sort of power or secret. Maybe it has a connection to the Sage of Six Paths. Naruto, being his curious self, would likely start to explore it. He might find strange markings or artifacts inside that he has never seen before.
One common plot is Kushina finding Naruto in a different time or dimension. For example, she might end up in the future where Naruto has grown up and she gets to see the kind of person he has become. It's an emotional and interesting concept as she gets to witness all his achievements and the challenges he has overcome.
Naruto could develop a more refined and sophisticated side. The suit symbolizes a new level of maturity. He might become more aware of the political and diplomatic aspects of being a ninja leader. For example, he starts to use more words and less brute force in negotiations.
There are various scenarios that could play out in such a fanfiction. Maybe Naruto was injured during a mission and Kiba stumbles upon him in the forest. Kiba would then likely try to help Naruto, either by getting medical help or using his own skills if he has some knowledge of healing. This could lead to a deeper bond between them as Kiba shows his concern and Naruto is grateful for the assistance.
It could be that the zanpakuto was brought into Naruto's world by some sort of interdimensional rift. Naruto, being curious and always eager to grow stronger, is immediately drawn to it. His godlike perception allows him to sense the latent power within the zanpakuto. He might seek out help from characters who have some knowledge of different power systems, like Kakashi. Together, they could try to decipher the mysteries of the zanpakuto, leading to Naruto adding yet another powerful tool to his already impressive arsenal.
Well, in a fanfiction where Naruto finds a morpher, it could lead to some really interesting crossovers. Maybe he'd use the morpher's powers in the Ninja world. He might initially be confused by it, but being Naruto, he'd quickly adapt and start exploring what he can do with it. It could potentially change the balance of power in his own world or even lead to him having to defend his world from new threats that the morpher's existence might attract.
One idea could be that the baby is from a hidden clan. Naruto decides to protect the baby from those who would use its special abilities. He takes the baby under his wing and trains it as it grows up, passing on his ninja values.