Well, one possible plot could be that Naruto is cursed by an enemy during a battle. This curse takes away his voice. As a result, he has to find new ways to communicate with his friends and allies. Maybe he starts using sign language, which he has to learn quickly. This could lead to some really interesting character development as he struggles to convey his thoughts and emotions without speaking.
One possible plot could be that Naruto is put under a powerful genjutsu. This genjutsu messes with his mind and slowly drains his emotions. As a result, he becomes detached from his friends and his sense of purpose. He no longer shows excitement for training or fighting, and his usual determination fades away.
In such a fanfiction, one possible plot could be that Naruto is exposed to some dark magic or a powerful curse that gradually erodes his humanity. This might lead to him becoming cold and detached from his friends. He could start making decisions that go against his normal moral code, perhaps being more ruthless in battle or in his relationships. The yaoi aspect might come into play if another male character tries to bring back his humanity through a deep emotional and physical connection with Naruto.
It could be that Naruto discovers some dark secrets about his past, like his parents were actually killed by the very people he trusted in the village. This revelation is so shocking that it shatters his mental state. He becomes a completely different person, losing his sense of right and wrong, and his sanity along with it.
The Akatsuki could be the main antagonists. They might think that Naruto's voice holds some key to a powerful weapon or secret. So they send one of their members, like Zetsu, to steal Naruto's voice. Zetsu's ability to blend in would make it easier for him to get close to Naruto and carry out the deed.
A 'Naruto loses his memory fanfiction' might involve a mysterious curse placed on Naruto. He forgets not only his personal relationships but also his ninja skills. His sensei, Kakashi, could take it upon himself to reteach Naruto everything from the basics. Meanwhile, Naruto might form new, unexpected relationships with people in the village who don't know the 'old' him, and these new relationships could either help or hinder his journey to regain his memory.
Maybe Orochimaru manages to get his hands on Naruto and subjects him to some dark and twisted experiments. These experiments could mess with Naruto's mind, causing him to lose his sanity. He could start seeing illusions all the time, believing his friends are his enemies. As a result, he'd be in a constant state of confusion and aggression, and his once - positive attitude towards life and ninja - hood would be completely gone.
Maybe he loses his humanity as a result of a failed experiment. Some rogue ninja or a secret organization might try to enhance his power but end up corrupting his very essence. As a consequence, Naruto could start to show no mercy, lack empathy, and use his powers for destruction rather than protection.
In this fanfiction, there could be a villain who has the ability to manipulate Naruto's mind. The villain might use this power to make Naruto turn against the Hidden Leaf Village. Naruto, without control of his own mind, could start causing chaos within the village, like attacking important buildings or trying to steal important ninja secrets.
In such a fanfiction, perhaps Naruto could be wrongly accused of something that leads to him being stripped of his birthright. Maybe a false claim about his connection to the Nine - Tails is used against him.
Well, perhaps the story could be about a character named Anxiety who is in a situation where he has to face a great challenge, like saving his friends or his world. But due to some magic spell or a very traumatic event, he loses his voice. This then makes it extremely difficult for him to communicate his warnings or ideas. Maybe he has to find a way to break the spell, and in the process, he discovers new strengths within himself that he didn't know before, like being able to communicate through telepathy with certain beings who then help him regain his voice and fulfill his mission.