One interesting plot twist could be that the Beast is actually a cursed prince from a rival kingdom, and the curse was placed by an evil sorcerer who wanted to start a war between their kingdoms. Another could be that Beauty has a hidden power that she discovers while in the castle, and this power is the key to breaking the curse in a completely unexpected way. Maybe she can communicate with the enchanted objects in a way that no one else can, and they reveal a secret about the curse.
Maybe Emma is actually from an alternate timeline where Regina was the one who sent her to our world for a greater purpose. As the story unfolds, this revelation makes Regina question her own motives and actions towards Emma throughout their time together.
Many fanfictions expand on their relationship by exploring their pasts. They might show how the Beast's life was before the curse, and how that affects his relationship with Beauty. Also, Beauty's family life and her upbringing can be delved into, which in turn helps to explain how she reacts to the Beast and how their relationship grows. For instance, if Beauty had a difficult family life, she might find solace in the Beast's company more quickly. And as for the Beast, his past experiences could make him more or less open to love, and these aspects are often explored in fanfictions.
One common plot twist could be that the pregnancy is a result of some magic gone wrong. For example, a spell meant for something else accidentally causes a character to become 'pregnant' with a magical entity. Another could be that the pregnancy is a way to save Neverland, like the new life will bring a power that defeats an evil force.
One interesting plot twist could be that Belle actually has a hidden power that she discovers while in the Beast's castle. This power could be related to time-travel, which ties into the 'Back in Time' aspect. Maybe she can manipulate time to prevent certain events from happening in the past, like the Beast being cursed in the first place.
One interesting plot twist could be that Hook is actually a long - lost relative of Peter Pan. Maybe they are related through some ancient magic or a family secret that was lost over time. This would completely change their dynamic, from sworn enemies to having a complex family - related relationship.
In some Beauty and the Beast pregnant fanfictions, a plot twist could be that the source of the Beast's curse is actually related to a prophecy about his future offspring. So, when Belle becomes pregnant, it sets off a chain of events that were foretold long ago. This could involve other magical beings coming to the castle to either protect or harm the baby. Another plot twist might be that Belle's pregnancy gives her the ability to communicate with the forest animals in a more profound way than before. They then become her allies in protecting the baby from any threats that may come from the dark corners of the enchanted forest.
One interesting plot twist could be that the Evil Queen is actually under a spell herself. In some fanfictions, it's revealed that a more powerful dark force has manipulated her into hating Snow White. Another twist might be that Snow White has hidden powers that she discovers during her time in the forest. For example, she could have the ability to communicate with animals in a more profound way than just them being friendly towards her. And a third twist could be that the dwarfs are not what they seem. Maybe they are actually guardians of an ancient magic and Snow White's arrival was fated to unlock that magic.
One idea could be exploring the backstories of the lost boys in more detail. Maybe one of them has a hidden connection to a character from the outside world. Another plot could involve a new villain coming to Neverland who has a different kind of magic that challenges Peter Pan. Also, a story about Wendy's granddaughter returning to Neverland to find a lost family heirloom could be interesting.
One common plot twist could be a character from Red Queen having different powers in the Once Upon a Time universe. For example, Mare might have an unexpected connection to a magical object in Storybrooke.
One interesting Once Upon a Time reaction fanfiction could be one where the characters react to modern technology. It's fascinating to imagine how Snow White would react to a smartphone or how Rumplestiltskin would deal with a computer. Another could be their reactions to different versions of their own stories from other fairy - tale collections. There are also reaction fanfictions where they react to changes in their own Enchanted Forest, like new magical creatures arriving.