It could also be a character within the pride who is jealous of Kovu's special connection to Scar (even if it's an unwanted connection). This character might spread rumors and try to turn the other lions against Kovu, creating a lot of internal conflict within the pride and making that character the main source of trouble for Kovu in the fan fiction.
One idea could be exploring what would happen if Scar had a secret plan for Kovu before his death. Maybe he left behind some instructions for Kovu to take over the Pride Lands in a different way than Simba's rule. Another could be a story where Kovu discovers a hidden connection between him and Scar, like they are related in a way no one knew. This could lead to a conflict within Kovu as he tries to figure out his true place in the Pride Lands.
Well, in the 'Lion King 2 Kovu Story', first, Kovu is introduced as a young lion being groomed for revenge by the Outsiders. Then, when he meets Kiara while she is on an adventure outside the Pride Lands, it sets in motion a series of events. As they interact more, there is growing suspicion from Simba towards Kovu. But the biggest event is probably when Kovu decides to go against the Outsiders' original plan and instead work towards peace. This decision ultimately leads to the resolution of the conflict between the two lion groups.
It could be Scar. Since he is the main villain in The Lion King, in a fanfiction where Shirou enters this world, Scar would still be the one causing trouble for the pride. He might see Shirou as a threat to his plans of taking over the kingdom.
Kiara and Kovu's love story is one of unity between two different worlds. They initially meet and there is an attraction. Despite the enmity between their prides, their love grows. Kovu was sent to get close to Kiara for a purpose, but he truly falls for her. Eventually, they overcome the differences and prejudices of their respective groups to be together.
It could be someone who wants to use Naruto's connection to the scar for their own evil purposes. Maybe a rogue ninja who believes that the scar holds some kind of dark power that can be harnessed.
Well, Scar from 'The Lion King' is quite a character. He has this green - eyed envy towards Mufasa. His appearance, with that scar on his face, gives him an intimidating look. His story is one of betrayal and greed. He wants the throne so badly that he is willing to sacrifice his own family. He first gets rid of Mufasa in a cruel way. Then he tries to rule the Pride Lands but fails miserably. The hyenas, who he thought were his allies, turn on him when things go wrong. And finally, he meets his end at the paws of Simba when Simba comes back to claim his rightful place as king.
Well, Scar in The Lion King has a very interesting story. Scar is kind of the outcast in the pride. He's not as strong or as respected as Mufasa. His jealousy drives him to make a deal with the hyenas. He lures Mufasa into a stampede and kills him. After that, he tries to rule but he doesn't really care about the Pride Lands. He just wants power. When Simba comes back, Scar tries to fight but his own evil deeds catch up with him and he loses.
Scar is the villain in The Lion King. He is Mufasa's younger brother. Scar is jealous of Mufasa's position as king. He devises a plan to kill Mufasa and frame Simba. Scar convinces Simba to go to the elephant graveyard, which is a dangerous place. Then he arranges for the hyenas to attack. Later, Scar kills Mufasa in a stampede. Scar then takes over the throne and rules over the Pride Lands, but his rule is cruel and he lets the hyenas overrun the place. Eventually, Simba returns and challenges Scar. Scar tries to blame everything on the hyenas, but in the end, he is defeated by Simba and falls to his death.
It can make fans who love the original story feel disgusted. The original relationships in The Lion King are iconic, and this kind of fanfiction goes against the expected pairings. It may also cause division within the fandom, with some fans being against this kind of distorted view of the story.
Mufasa is good and noble, while Scar is evil and jealous.