Yes, there might be. The Naruto and Attack on Titan fandoms are both huge, and fans often like to cross over their favorite characters in fanfiction. So it's quite possible to find Eren - from Attack on Titan - in Naruto fanfiction. However, it may not be as common as fanfictions within each respective universe.
Crying could be described according to different situations and characters. There were a few possible ways to describe it:
1. Crying sadly: The eyes are red and swollen, and the tears are constantly flowing. The lips are slightly opened, as if they are silently pouring out the pain in their hearts.
2. Crying in despair: Tears poured out like a waterfall. His eyes were hazy and he looked depressed as if he had lost all his strength.
3. Crying angrily: The eyes are red and swollen, and the tears are like boiling flames. The expression on the face also becomes angry and resentful.
4. Crying in surprise: Tears instantly gushed out of her eyes as if expressing her inner ecstasy and gratitude.
5. Crying in fear: Tears flow from the eyes. The trembling body and helpless heart make people feel fear and uneasiness in their hearts.
Different crying forms could show the character's inner emotions and personality characteristics, and at the same time, it could allow the reader to better understand the character's psychological state.
I recommend Thank You For Our Time, which tells the story of Susan meeting her ex-boyfriend during the epidemic. Would the two of them still hold hands at the next intersection after going through the storm? The female protagonist and the male protagonist had met before. When the female protagonist broke up with her boyfriend, the male protagonist was still present and heard the female protagonist's words. I hope you like my recommendation.
Some fans are heartbroken. Eren is a very popular character, and his death can be a huge emotional blow. They might write comments expressing their sadness and disappointment.
Fanfiction about Eren and Levi kissing can be quite interesting. It might explore a different side of their relationship. Some fanfictions in this regard could be about a moment of emotional intensity between them, where the kiss represents a deep connection that goes beyond their usual interactions in the original story.