In some cases, Sasuke could be angry. He might see Naruto's request as a sign of weakness or as Naruto giving up too easily. He could lash out at Naruto, telling him to fight instead of asking for death. However, he would still be deeply troubled by the request and would probably struggle with it for a long time, constantly thinking about whether or not he should consider it.
He could also be initially confused. Sasuke has known Sakura for a long time, and this unexpected act from her would leave him wondering about her motives. He may hold back his anger for a while to hear her out and understand why she did such a thing.
Naruto would probably be really angry at first. He's a free - spirited person who doesn't like being forced into things. So he'd likely try to fight back right away, yelling at Sasuke about what he's doing.
He might be initially confused. Sasuke is not used to Sakura ignoring him as she has always been somewhat persistent in her attention towards him. So, he may be at a loss as to why she is suddenly acting this way.
There are fanfics where Sasuke is a bit more reserved in his reaction. He may not show extreme emotions outwardly but instead, internally he's filled with a mixture of excitement and fear. He might start thinking about all the responsibilities that come with having a child and how his life as a ninja will need to change to accommodate this new addition to his family.
Naruto would probably be excited at first. He has always wanted to help Sasuke and this would be a great opportunity for him to do so. He'd be eager to share his skills and knowledge.
On the other hand, Sasuke could be a bit confused. He might not understand why Naruto, who has been his friend in the past, is refusing to teach him. This confusion could lead to him re - evaluating their relationship and trying to figure out what he has done to deserve this treatment. He may start to question his own actions and motives more deeply.
Naruto might initially be in denial. He's so used to having Sakura around and believing that they have a future together. So when she leaves for Sasuke, he might think it's just a temporary thing or that she's been influenced by something or someone. But as time passes and he realizes it's real, he would be deeply hurt. He might also start to question his own self - worth, thinking that he wasn't good enough for Sakura. And he might even try to win her back at first, but then slowly come to accept the situation and focus on his other responsibilities like being a ninja and protecting the village.
Naruto could also feel a sense of confusion. He might wonder what he did wrong or what made Fem Kyuubi choose Sasuke over him. This confusion could lead him to question his own worth and his relationships with others. However, in true Naruto fashion, he would eventually rise above these negative feelings and focus on his goals, like protecting the village and his friends.
Sakura might initially be shocked and resistant. She is a strong - willed character, so she could try to fight back or find a way to escape this forced situation. Maybe she would first confront Sasuke about his unacceptable behavior.