Yes, unfortunately, Hange met their end in the manga. It was a poignant moment for fans. The circumstances leading to their death were quite intense and had a significant impact on the story.
Zoe could become more withdrawn initially. Losing Percy, who was perhaps a close friend or love interest, would be a huge blow. But then, she might slowly turn her grief into strength. For example, she could become more determined in her fights, using Percy's memory as a source of inspiration.
Survival and sacrifice are themes that can be found as well. In the world of Attack on Titan, survival is not guaranteed. Fanfictions may depict situations where Moblit has to sacrifice himself to save Hange or vice versa. This adds a layer of drama and emotion to their relationship. It shows the depth of their bond, that they would be willing to give up their lives for each other in the face of the Titans.