General Zod and Doomsday are not the same. General Zod is a Kryptonian villain with his own distinct traits and motives, while Doomsday is a powerful and destructive creature. They have different origins and storylines in the comic universe.
One great 'Young Justice General Zod Fanfiction' is 'Zod's Ascent'. It shows General Zod arriving on Earth in the Young Justice universe and his attempts to conquer it in a really unique way. The author does a great job of portraying Zod's power and his military - like strategies.
One frequent theme is redemption. Some fanfictions attempt to give General Zod a chance at redemption. They might show him being influenced by the Young Justice team's ideals of justice and heroism, and slowly changing his ways. Also, the theme of leadership is common. Zod is a natural leader, and fanfictions explore how his leadership style clashes or meshes with the leadership in the Young Justice universe.
In certain comic versions, Superman is forced to take the extreme measure of killing Zod due to the circumstances and threats posed. However, this action often has significant consequences for Superman's character development and moral conflicts.
In certain comic arcs, Superman was forced to take that extreme action against Zod due to the circumstances and threats posed. It was a complex and controversial moment in the comics.