A fanmade Alternate Universe of Steven Universe where Steven is not the son of rebel leader Rose Quartz, but rather the son of Blue Diamond. This leaves Steven in the care of his father, Greg, and Blue Diamond's Pearl.
The Crystal Gems start out as a bogeyman for Steven to avoid, fearing what might happen to him if they ever discovered his existence, only to later become their allies with what threatens Earth.
Can be considered a sub-category of Momswap AU.
Examples of fan works set within the Blueswap format include:
Tropes usually used in Blueswap include:
- Ascended Extra: Since Blue Pearl is the only gem to accompany Blue Diamond on her personal quests to Earth, she is usually there to fill the role as maternal figure to Steven throughout his life.
- Innocent Blue Eyes: Steven is given bright blue eyes to help distinguish him as Blue Diamond's son, while keeping his chipper and innocent personality.
- In Spite of a Nail: With the reveal that Steven Universe was actually the son of Pink Diamond in "A Single Pale Rose", this would mean that canon Steven and Blueswap Steven are both sons of Diamonds.

