In fanfiction, there might be external forces against Naruto's plan. For example, some secret organizations or anti - village groups may try to stop Naruto from getting Sasuke back to the village. They might see Sasuke as a valuable asset for their own malicious purposes.
Another challenge could be Naruto's own doubts. Even though he wants to find and take in Sasuke, he may question whether he can really change Sasuke or if Sasuke will just leave again. This internal struggle can also make the process of finding and taking in Sasuke more difficult in the context of fanfiction.
One challenge could be Sasuke's resistance. Sasuke might be so set in his own ways that he doesn't want to be 'taken in' by Naruto. He may see Naruto's attempt as an intrusion on his freedom.
Sasuke might face the challenge of understanding baby Naruto's needs. Since he's not used to dealing with infants, things like feeding, changing diapers could be really difficult for him.
Well, for starters, Kakashi has to deal with Naruto's hyperactive and sometimes reckless behavior. Naruto often acts without thinking, which could put him in danger. Sasuke, with his complex emotions and the burden of his clan's massacre, is also a handful. Kakashi needs to make Sasuke understand that revenge is not the only way forward. Additionally, Kakashi has to ensure that both Naruto and Sasuke get along well with each other. There could be rivalry between them, and Kakashi has to manage that in a way that doesn't harm their relationship or their growth as ninjas.
One challenge could be time management. Naruto is always so busy with his ninja duties, protecting the village and going on missions. Finding the time to sit down and write would be tough. Also, he might struggle with grammar and spelling since his ninja training didn't really focus on that.
One challenge could be gaining the trust of the Root members. Since Root has a history of being a secretive and somewhat feared organization, the members might be skeptical of Naruto's leadership. They're used to a more authoritarian style, and Naruto's more open and friendly approach could be met with resistance.
In a fanfiction, after their wedding, Sasuke and Female Naruto might face the challenge of balancing their duties. Naruto might want to focus on village improvements while Sasuke may be more interested in security matters. This difference in priorities could lead to arguments. Also, Sasuke has a dark past that still haunts him at times. His nightmares could potentially affect their relationship. Moreover, they will have to deal with the expectations of the village. People will look up to them as a couple, and any mistake they make could be highly scrutinized, adding stress to their married life.
They could face challenges from the ninja world's authorities who might see them as deserters. Other villages might try to capture them to gain an advantage over Konoha.
Financial aspects can be tough. Pets need food, toys, and sometimes veterinary care. The cabin also requires maintenance, like fixing a leaky roof or buying new furniture. If the family budget is tight, the wife has to be really creative in making sure everything is taken care of. Also, in case of bad weather, like a heavy snowstorm, she has to ensure the safety of the pets and protect the cabin from damage, which is no easy feat.
One challenge could be adapting to the team's dynamics. Team 8 has its own way of operating, and Naruto is used to his own style with his friends. For instance, they might be more methodical in their planning, while Naruto is more of a 'jump - in - and - figure - it - out' type. So, he'd have to learn to follow their lead sometimes.
One challenge could be controlling the amount of natural energy he uses. If he uses too much, he might lose control and enter a berserk state like when he first tried to use Sage Mode. Another challenge is that his opponents might find ways to disrupt his connection to natural energy sources, leaving him weakened.
One challenge could be overcoming his natural inclination towards ninjutsu and taijutsu. Since he's always been more focused on those areas, switching his attention to genjutsu might be difficult.