Perhaps a character from a post - apocalyptic world. They could have a very different perspective on Lincoln's bad luck. In their world, they've faced much worse, so they might initially dismiss it as not that big of a deal. But as they get to know Lincoln and his family, they start to understand the emotional toll it's taking on them and help them find solutions in ways that are unique to their survival skills.
How about a character from a classic fairy tale? For instance, Cinderella could be accidentally brought into the 'The Loud House' world during the crossover. Her presence could contrast with the chaos of Lincoln's bad luck. She might try to use her positive attitude and her experience with hardships to help Lincoln deal with his situation.
If you're doing a crossover with 'Scooby - Doo', Scooby and Shaggy are must - includes. They could bond with the Loud family over food and then get caught up in a mystery in Royal Woods. Velma could use her smarts to solve the mystery, and Fred could lead the way with his trap - making skills. Daphne could also befriend the Loud sisters and add some charm to the story.
The Doctor from Doctor Who would be an interesting addition. He could land his TARDIS in the jungle and get involved in the jungle's affairs. He might help Mowgli and the animals deal with a time - related threat, like a time - traveling villain who wants to change the history of the jungle.
One idea could be that the misfortunes from 'No Such Luck' somehow cross over into an alternate universe in the crossover. For example, Lincoln's bad luck could start affecting the other characters from the crossover world in strange ways, like causing their gadgets to malfunction.
Another plot might involve a character from the 'bad luck' side of the crossover coming to the Loud House world and bringing their bad luck with them. This could disrupt the normal family dynamics. The Loud siblings would then have to figure out how to get rid of the bad luck and restore order. They might try all sorts of wacky plans, like using their own unique skills and talents in a new way to combat the bad luck.
One idea could be a crossover with another popular animated show. For example, the characters from 'Loud House' could end up in a different universe where they have to use their unique skills from 'No Such Luck' to survive. Maybe they meet characters who have similar family dynamics but different challenges.
For Lincoln in this crossover, you can focus on his resilience from 'No Such Luck'. Despite all the bad luck he had, he still tried to keep a positive attitude. In the crossover, put him in difficult situations where he has to use that same tenacity. For example, if they cross into a dangerous new world, he could be the one motivating the others.
Sometimes, even the family pets or the neighbors can be focused on in fanfictions related to this episode. They could be the ones who help Lincoln figure out what's really going on with his bad luck or they could be affected by his luck in some comical ways.
The Care Bears. It would be really unexpected to see the cute and cuddly Care Bears in the dark and violent world of Twisted Metal. Maybe they could be there to try and bring some peace and love, but end up getting caught in the crossfire between the Twisted Metal drivers.
Sherlock Holmes could be an unexpected character in Pinocchio crossover fanfiction. Holmes could use his deductive skills to figure out why Pinocchio's nose grows when he lies and might even try to find a way to control it. Another one could be Alice from Wonderland. Her strange adventures in Wonderland and Pinocchio's own adventures could combine in interesting ways, like exploring a new and magical land together.
Leni and a bad - luck character who is always in a hurry to fix things but just makes them worse. Leni's somewhat oblivious but kind - hearted nature could either be a hindrance or a help. They could get into all sorts of misadventures together, like trying to fix a fashion disaster that the bad luck caused, but instead creating an even bigger mess.