Well, perhaps it could be about a powerful human wizard who accidentally casts a spell on the MLP characters and turns them into babies. Then the story might focus on how the other ponies in Equestria have to take care of these baby versions and try to find a way to reverse the spell.
It could be that a human scientist creates a machine that has an unexpected side effect of transforming the MLP into infants. The plot may then revolve around the human feeling guilty and trying to collaborate with the ponies' friends to bring them back to normal. They might face various challenges along the way, like dealing with the different personalities of the baby ponies and finding the right components to fix the machine.
Maybe in this fanfiction, a human discovers a magical artifact that, when touched, turns the MLP into babies. The story could be about how the ponies' families and friends first react with shock but then come together to raise the baby ponies. There could be cute moments of the baby ponies learning basic things like walking and talking again, and a big adventure could be centered around finding the origin of the artifact to reverse the transformation.
It could be one of the baby ponies themselves. Maybe the story could be told from their perspective as they experience the world in this new, baby - like state and how they interact with their friends and family who are now taking care of them.
One possible plot could be that the MLP discovers a mysterious ancient spell. When accidentally casting it, it starts to transform into a dragon. At first, it's scared but then realizes it has new powers like flying and breathing fire. It has to learn to control these powers while also facing the reactions of its pony friends, some of whom are afraid while others are curious.
Well, perhaps the human could be transported into the My Little Pony world and gradually take on the characteristics of Twilight. Maybe they start by learning magic like Twilight does, and as they do, they become more like her in personality too, like becoming more studious and dedicated to knowledge.
One possible plot could be that an AI, after some kind of malfunction or experimental procedure, gains human form. In the lemon fanfiction context, perhaps it finds itself in a romantic or sexual situation. It might struggle with new human emotions like love and lust that it has never experienced before as an AI. It could be attracted to a human character and have to navigate the complex world of human relationships while also dealing with its own identity crisis.
Well, it immediately creates a big change in the character's situation. They go from being a human with all the associated skills and knowledge to a pony with different physical abilities. This can lead to a lot of comical moments as they adjust, like trying to walk on four legs instead of two. It also often sets up a journey of self - discovery as they figure out who they are now as a pony.
A possible plot could be that a human soldier gets lost in the mlp world. He has to adapt to the new environment which is very different from his own. He could use his combat skills to protect the ponies from a common enemy, like a dragon. As he stays longer, he starts to understand the pony culture and values, and in turn, the ponies learn about human courage and tenacity.
In some fanfictions, a human who is turned into a pony might have to deal with the social structure of the pony world. They might find that there are different pony tribes and they have to figure out where they fit in. Some ponies might be suspicious of this new pony who seems to have strange behaviors from a human world, but eventually, through kindness and understanding, the turned - pony human finds their place.
The plot might involve the male human being ill or cursed. Zecora, as a healer, tries to find a cure for him. This could lead to a series of adventures as they search for rare ingredients for the cure. They might face various obstacles in the forest, like dangerous animals or magical barriers, and they have to rely on each other to overcome them.
In some fanfics, a human turned into an MLP character might discover hidden powers within themselves. For example, they could be turned into a unicorn and realize they have an extraordinary ability to heal, which then leads them on a quest to use this power for good and gain acceptance in the pony community.
In this fanfiction, it could be that a mad scientist creates a device that emits a ray which affects the Turtles' DNA, causing them to regress into babies. Their personalities remain somewhat the same, but they now have to deal with the limitations of being infants. Their brothers' relationships change as they now have to be more protective. For example, Raphael, who is usually tough, has to be extra gentle with his baby brothers. And they all have to figure out how to get back to their normal forms while still being cute little baby Turtles.