I Turned into a Little Girl and Somehow Became the Primordial Witch

Crossover anthology + chat group + pseudo-transformation + invincible protagonist + urban superpowers, featuring lots of anime and urban superpower settings.

So far, the series featured include K, No Game No Life: Zero, Golden Mosaic, That Time I Got Reincarnated as a Slime, Mushoku Tensei, Love, Chunibyo & Other Delusions, Puella Magi Madoka Magica, Date A Live: Mayuri Judgment, Demon Slayer, Katekyo Hitman Reborn!, Onii-chan wa Oshimai!, Dr. Stone: Stone Wars, The Aquatope on White Sand, Talentless Nana, The Journey of Elaina, Anohana: The Flower We Saw That Day, Re:Zero − Starting Life in Another World, Magical Girl Lyrical Nanoha, and Gabriel DropOut. Next, I’m planning to add Fire Force, So I’m a Spider, So What?, Angel Beats!, or Cardcaptor Sakura.

World wills: “Witches are the darlings of the world, and Rei is the primordial witch we’ve chosen. You could say she’s loved by every world. Even the birth of new witches and the powers granted to them are in her hands. If she doesn’t want any new witches to appear, then no new witches will ever be born.”