One great 'Naruto Momoshiki Otsutsuki fanfiction' is 'The Otsutsuki's Ascent'. It delves deep into Momoshiki's backstory and his interactions with the Naruto universe in a really interesting way.
Power is a common theme. Since Momoshiki is such a powerful character, many fanfictions explore how his power affects the Naruto world and the characters in it.
There's a really interesting one where the author gives a different perspective on the fight. It's called 'Naruto and Sasuke vs Momoshiki: An Alternate View'. It focuses more on the strategic aspects of their combat that the anime might not have fully explored.
It's appealing because we get to see more of the characters' thoughts and feelings during the fight. In the original series, there are limitations on how much of their internal monologues can be shown. Fanfictions fill that gap. For example, a fanfiction might show Naruto's doubts and how he overcomes them during the battle with Momoshiki. Also, some fanfictions might explore different relationships between Naruto, Sasuke and other characters in the context of this battle, like how their teamwork affects the fight in ways not shown in the anime or manga.
As of now, Naruto and Sasuke haven't died in the Boruto manga. Their characters continue to play significant roles and contribute to the story's development.
It depends on the context. If it's a battle of pure physical strength and chakra, Naruto might have the edge as he has years of experience and has faced more powerful foes. But Boruto has some unique abilities like his Jougan. So if the fight involves using new - age ninja techniques, Boruto could surprise Naruto.
I like Naruto in these fanfics because he always stays true to his beliefs. He is constantly trying to bring Sasuke back to the village and is willing to fight for their friendship.