Well, a possible plot point is how they deal with the various challenges in Equestria. Maybe they encounter a dangerous creature and have to use their unique human skills, like problem - solving in a different way than ponies do, to overcome it. Also, their relationships with the pony counterparts of their friends in the human world could be really interesting. They could discover new sides to their friends' personalities.
One interesting plot point could be the culture shock the Equestria Girls experience when they first arrive in Equestria. They might be amazed by the magic that is so commonplace there but strange to them. Another could be their interactions with the ponies. For example, they might have to learn new ways of communication and social norms.
In this fanfic, a great plot point could be the Equestria Girls' attempts to fit in. They are in a world full of ponies with different abilities and appearances. They might try to participate in pony activities like the Grand Galloping Gala. Their fashion sense from the human world could also have an impact, either being a source of fascination or confusion among the ponies.
The main characters are likely to be the Equestria Girls themselves. Twilight Sparkle from the human world would be a central figure as she often takes the lead in many situations. Then there are her friends like Rainbow Dash, Pinkie Pie, etc. Also, the pony versions of these characters might play important roles as they interact with their human counterparts.
One idea could be an OC who is a new student at Canterlot High. She has a unique power related to music, like she can make people feel different emotions through her singing. And she gets involved in a battle of the bands where there's some sort of mystery or magic influencing the competition.
The plot is mainly about the pony - turned - human girls in Equestria Girls Story. They experience adventures in their human forms. There are elements of friendship, like how they support each other through various difficulties. Also, there are often antagonists who try to disrupt the harmony among them or steal the magic they possess.
Maybe there's a villain from the MLP world that follows them into the Equestria Girls world. The girls then have to team up with their Equestria Girls counterparts to defeat this villain. They could combine their different skills, like the pony Rainbow Dash's speed in the air and the Equestria Girls Rainbow Dash's skills on the track team.
One idea could be that Sonic accidentally enters the world of Equestria Girls while chasing Dr. Eggman through a strange portal. He then teams up with the girls to stop Eggman from stealing the magic that powers their world. Another could be a race between Sonic and Rainbow Dash which gets interrupted by a common enemy.
One interesting concept could be the role - reversal of the characters' personalities. For example, a usually shy character becomes bold and confident. Another concept might be the swap of their magical abilities or talents. It can lead to really unique storylines where characters have to adapt to new powers. Also, the change in relationships between characters can be fascinating. Characters who were friends might now have a different dynamic due to the swap, like becoming rivals or having a more mentor - mentee type of relationship.
One interesting plot could be the characters facing unexpected challenges during graduation, like a last - minute project that tests their friendship. Another might be a character having to choose between different post - graduation opportunities, creating some drama. And perhaps there could be a mystery that unfolds during the graduation ceremony itself.
There might be a reaction fanfic where they react to a new villain in their world. They would have to figure out how to deal with this threat, and their reactions could range from shock to determination. For example, Twilight Sparkle might immediately start researching about the villain's powers while Rainbow Dash is ready to take on the challenge head - on.
One possible plot could be that the Equestria Girls characters somehow get transported into the XCOM universe. They then use their unique pony powers, like Twilight's magic or Rainbow Dash's speed, to help XCOM in their fight against the alien invaders. For example, Twilight could use her magic to disrupt alien technology.
One idea could be a crossover where Shadow meets the Equestria Girls during a magical event in their world. Maybe he has to team up with them to defeat a common enemy that threatens both his world and theirs.