One idea could be that Thomas the Tank Engine somehow ends up in Equestria. Maybe there's a magical portal that transports him there. He could then interact with the ponies, perhaps helping them with some big construction project like building a new bridge. The contrast between his mechanical world and the magical world of MLP would create a lot of comical and interesting situations.
Transformation can also be a theme. Maybe a Thomas character gets transformed into a pony - like form in the MLP world or vice versa. This can lead to humorous situations as they try to adapt to their new forms and the rules of the new world. It also allows for exploring how their identities change and how they are perceived by others in this new state.
Both sets of characters could develop through friendship. A Thomas character like Percy could make friends with a shy pony. Percy's friendly nature could help the pony come out of its shell. At the same time, the pony could teach Percy about the joys of magic and nature. This mutual exchange of ideas and experiences would lead to the growth and development of both characters in the crossover fanfiction.
Thomas and Twilight Sparkle. Thomas is a simple, hard - working engine, while Twilight is a studious and powerful unicorn. Their different natures could lead to some really interesting interactions. For example, Thomas could teach Twilight about the value of physical work and Twilight could introduce Thomas to the magic of knowledge.
Once upon a time, Mario found himself in the magical world of MLP. He was quite confused at first, with all the colorful ponies and floating castles. But being the brave hero he is, he decided to explore. He met Twilight Sparkle, who was intrigued by this strange new being. Mario showed her his jumping skills, and Twilight was amazed. They then went on an adventure together to find a way to send Mario back to his world, facing all kinds of challenges along the way, from evil magic spells to tricky terrains.
Some popular Thomas MLP fanfics might include those that combine the unique worlds of Thomas the Tank Engine and My Little Pony in interesting ways. For example, there could be fanfics where the characters from both universes meet and have adventures together. It could involve Thomas and his friends exploring the colorful and magical land of Equestria from MLP, or the ponies coming to the railway world of Thomas.
First, think about the basic plot. Decide if it's a crossover where the two worlds interact, or if it's just one character from one series in the world of the other. For example, if you want to write about Pinkie Pie in Sodor, consider what she would do there. Maybe she'd throw parties for the trains. Then, create an outline of the story. Start with an introduction that sets the scene, like Pinkie Pie arriving on Sodor by a magical portal.
I really like 'The Avengers in Equestria' which is a part of 'mlp fim crossover fanfiction'. It has the Avengers characters somehow transported to the world of My Little Pony. It's full of action and also shows how the ponies and the superheroes deal with their differences and work together. It's a fun read for fans of both franchises.
Well, there's a Thomas crossover fanfiction that combines it with 'The Lord of the Rings'. In this story, Thomas might be on a quest through Middle - earth, facing orcs and other perils. Some fanfictions cross Thomas over with superhero universes. For example, Thomas could be helping the Avengers with a mission that requires his unique locomotive skills. It's really interesting to see how different universes collide in these fanfictions.
Friendship is another big theme. When different characters cross over, they form new friendships. For example, in a crossover with another popular series, the characters start off as strangers but end up relying on each other and becoming great friends through shared adventures.