In the fanfiction, Kakashi might face the challenge of Naruto's insecurities. Naruto has always had a complex about being alone and not having a family. Kakashi would have to find ways to make Naruto feel secure and loved. Also, dealing with Naruto's powerful and sometimes uncontrollable chakra could be a problem. Kakashi would need to train Naruto to master his chakra properly without it overwhelming him.
The expectations of the village could be a big challenge for Kakashi while raising Naruto. The village has high hopes for Naruto, seeing him as the potential savior or a great ninja. Kakashi has to ensure that Naruto lives up to those expectations without breaking under the pressure. Moreover, he has to protect Naruto from any threats that might come his way because of his special status. This includes not only physical threats but also political ones within the ninja village.
In the fanfiction, Kakashi might raise Naruto with strict ninja training. He would instill in Naruto the importance of discipline, as he himself is a disciplined shinobi. He'd teach Naruto various jutsu, starting from the basics like the Clone Jutsu, but with his own unique spin on the training methods.
One challenge Naruto might face is Gaara's past traumas. Gaara has been through a lot of pain and isolation, which has made him distrustful. It would be difficult for Naruto to break through those barriers and get Gaara to open up. Another challenge could be the political situation. Suna and Konoha have had their differences in the past, and some in Suna might not be happy with Naruto's influence on Gaara. Naruto would have to deal with any potential political unrest or opposition from those who don't trust Konoha.
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 Naruto's impulsive nature. He often rushes into things without thinking, and Tsunade would have to find a way to rein him in. Another might be dealing with Naruto's fame. Since he is the Jinchuriki of the Nine - Tails, he has a lot of attention on him, and Tsunade would need to protect him from those who might want to use or harm him.
Financial difficulties could also be a problem. Naruto might not be well - off initially, and raising a child requires money for things like food, clothes, and education. He would have to find ways to provide for his sister while still being a ninja. Also, there could be threats from Naruto's enemies who might try to target his sister to get to him.
One challenge could be the public perception. The wizarding world may not be very accepting of Hermione raising Voldemort's daughter. There could be a lot of fear and suspicion. Another challenge is Delphini's own nature. Since she has Voldemort's blood, she might have some inborn dark tendencies that Hermione has to constantly fight against. Also, Hermione would have to deal with the memories and legacy of Voldemort that might be a part of Delphini's upbringing.
One challenge could be dealing with their different personalities. Each sibling might have their own desires and goals. For instance, one might be more interested in military matters while another in the arts. Rhaenyra would have to find a way to nurture all of them individually.
One challenge could be finding enough Uzumaki descendants. Since the clan has been through so much, there may be very few left. Another might be dealing with the political implications. Other clans might be jealous or fearful of a resurgent Uzumaki clan.
One of the main challenges is time management. The Chunin Exams are approaching fast, and Naruto has a lot to learn. He has to quickly grasp complex ninja techniques that Kakashi is teaching. Another biggie is dealing with his own impatience. Naruto is eager to prove himself and might rush through the training, not fully absorbing the lessons.
One challenge could be time management. The adventurer has to balance exciting and often dangerous adventures with the daily routines of parenting like school runs and meal times. For example, if they are called away on a sudden adventure, they might have to quickly arrange for someone to look after the kids.