Some Pokemon might show excitement. For example, Pikachu could be all energetic, jumping around as if it's happy to be part of the fanfiction world. It might use its electric attacks in a celebratory way, like creating little sparkles in the air.
The son might initially be very confused and resistant. He has his own sense of identity as a boy, and being forced to be a girl goes against that. He could try to rebel by doing more boy - like things in secret.
On the other hand, the son might try to adapt in a way to please his mom at first. But as time goes on, he will likely start to feel a great internal conflict. He might start to secretly explore his true identity while still pretending to be a girl for his mom. This could lead to a lot of secrecy and emotional turmoil within him as he tries to balance his true self and his mom's expectations.
The son might initially be very confused. He's a boy and being forced into a 'daughter' role is something completely alien to him. He may resist, not understanding why his mom wants him to do this.
Some in the ninja world would likely be shocked at first. The idea of Naruto and Sasuke having a son together goes against the traditional views of many. But those who are close to them, like their friends from Team 7, would probably be supportive. Kakashi, for example, might see it as a new step in the evolution of the ninja world's relationships. However, there would also be those who oppose it, especially from more conservative clans who might fear the implications of such an unorthodox union on their power structures.
There are also sons who might initially be hesitant but then get used to it. For example, if the mom explains the situation well, like it's just for a one - time game or for a creative project. The son may start to enjoy the new look and feel more comfortable as time goes on.
The son might feel mortified. He may not know what to say at first. But he should try to stay calm and not run away or act defensively. He can later have an honest conversation with his mother about how he understands it was inappropriate to do it in a place where he could be caught, and also learn from her about privacy and healthy sexual habits.