Well, a really cool 'the mandalorian crossover fanfiction' concept would be a crossover with the Halo universe. The Mandalorian's combat skills and armor could be contrasted with the Spartans' abilities. Maybe they have to fight a common enemy that has invaded both their universes. Or perhaps a crossover with the Lord of the Rings. The Mandalorian could find himself in Middle - earth, having to deal with orcs and other dark forces while trying to find his way back to his own galaxy.
One idea could be a crossover with Star Wars Rebels. The Mandalorian could team up with Ezra Bridger to take on a new threat in the Outer Rim. Another idea is a crossover with the Doctor Who universe. Imagine the Mandalorian meeting the Doctor and having to deal with some time - traveling villains together.
Perhaps there could be a lost Mandalorian artifact that the Rebels accidentally discover. This draws the attention of a group of Mandalorians who think the Rebels are trying to steal it. As a result, they have to work together to figure out the true purpose of the artifact and face off against a common enemy who also wants it for their own evil plans.
One idea could be exploring the backstories of the Mandalorian warriors. For example, how they were trained and what their family lives were like before the wars.
An OC that is a young Force - sensitive foundling. The Mandalorian could take this child under his wing, and the story could explore how they both learn from each other. The OC might struggle with controlling their powers, and the Mandalorian would have to protect them from those who would seek to use the child's power for evil.
Maybe in the fanfiction, Ezra has some unique skills or knowledge that the Mandalorian's harem finds useful. For example, he could have some understanding of ancient Jedi artifacts that are relevant to a mission they are all on. This could lead to interesting interactions and the development of relationships within the harem.
One plot idea could be Baby Yoda getting lost and the Mandalorian having to search through a dangerous planet full of strange creatures to find him. Another could be the Mandalorian teaching Baby Yoda some special skills or knowledge that is unique to his culture.
Well, a cool plot for a Star Wars Mandalorian SI fanfiction could involve the self - insert being a former Jedi in hiding. They could use their Jedi training secretly to help the Mandalorian and Grogu. Maybe they teach Grogu some new skills that are a blend of Jedi and Mandalorian ways. Also, the self - insert could have a past connection to the Sith, which adds an interesting layer of conflict as they struggle not to be drawn back to the dark side while helping the Mandalorian. Another idea is that the self - insert is an artist who uses their art to document the adventures of the Mandalorian, and in the process, their art gains some sort of magical or important significance in the Star Wars galaxy.
One interesting idea could be a crossover with "Moana". Elsa's ice powers and Moana's connection to the ocean could create a really cool dynamic. Maybe Elsa accidentally freezes part of Moana's ocean and they have to work together to fix it. Another could be with "Tangled". Rapunzel's long hair and her adventurous spirit combined with Elsa and Anna's journey in Frozen 2 would be exciting. Rapunzel could use her hair to help them climb mountains or cross chasms. A third idea is a crossover with "Beauty and the Beast". Belle's love for books and knowledge could help Elsa understand more about her powers and the history of magic in the Frozen world.
A Thundercats and Star Wars crossover fanfiction would be really cool. The Thundercats could be in the Star Wars universe, and their unique powers and weapons could be a great addition. Maybe the Thundercats could help the Jedi or the Rebels in their fight against the Sith or the Empire. For instance, Cheetara's speed could be useful in battles, and Tygra's illusions could be used to deceive the enemy.
One idea could be a story where the Mandalorian has to team up with an old enemy to fight a new, greater threat. Maybe a powerful Sith Lord emerges and they have to put aside their differences.
In this fanfiction, Ezra could be on a mission and stumbles upon an ancient Mandalorian artifact. This artifact has some sort of connection to the Force, which draws Ezra in. As he delves deeper into the Mandalorian culture to understand the artifact, he uncovers secrets that not only change his perspective on the Mandalorians but also give him new powers or knowledge that he can use against the Empire. The story could explore how Ezra balances his newfound Mandalorian - influenced identity with his role as a rebel and a Force - user.