What if Boku no Hero Academia instead took place in world that was more similar to Naruto's. Where instead of becoming Pro Hero, they were training to become ninjas instead. Quirks were justus and rather then Izuku getting justu based One for All or even a tailed beast. Instead he gets a more justu based version of the Eight Gates instead. (ideas & concepts subject to change)
In the episode, The Mirror, Elisa and then all of Manhattan were turned into gargoyles but quickly turned back before the night was over. What if everything did not end as swiftly though changes here and there prevent the battle & conclusion from happening before the sunrise. Thus while the majority of Manhattan is reverted a small group of others and Elisa are not changed back
In an alternate world where Ace and Yamato do not meet each other in their twenties but instead certain things happen. Things that alter fate and how things should have happened allowing Yamato and Ace to meet while they are both still kids. After growing up together, Yamato joins Ace when he sets out to become a pirate thus becoming the first member of the Spade Pirates.
Normally during his childhood, Issei Hyoudou would always play with Irina Shidou until she moved away. However that changed as one day, when the two of them befriend an amnesiac red hair girl that wonders into Kuoh Town. This simple act not only change the lives of the three of them but have cascading effect on the events that would happen in Kouh Town for years to come
Changing the past was what Chloe had attempted doing & failed at countless times before finally managing to succeed in the manner she wanted to. However preventing a certain event from happening could always come with unexpected consequences that you could have never expected. Chloe's success result in massive change in her original world & her childhood friend Izuku Midoriya too
A Shadow Cloaked Mage out there claiming to 'heal' others of things that even high level healing magic can not handle. Though the price being they turned into robots as result. Can the Black Bulls find out what happening in time or will they end up falling prey to the Shadow Cloaked Mage themselves. (Inspired by Squishy! Black Clover)
The events that take place in the life of one Cream the Rabbit as she is roboticized into a typical robian. Trying to describe how from her own POV, how she would live and possibly think as Cream the Robian, a robotic minion to her master Dr. Robotnik.
Kari, Davis,Tai, and Sora get turned into humanoid version of their digimon while their digimon get turned into humans.