Haha, yeah that would be funny!
Actually, I did make an acrylic painting last year of a Muppet/Steven Universe crossover with muppets as the Gems. In this version, I had Piggy as Garnet, Skeeter as Amethyst, Janice as Pearl and Robin as Steven. You can find it here:
http://iamallyballybee.deviantart.com/art/We-are-the-Muppet-Gems-459956537
I might do another version one day to match the show now but it's kinda an old favourite of mine.
Description
Landscape painting. Background consists of green and turquoise magic light beams, diamonds and sparkles very similar to the show's backgrounds. In the centre is Miss Piggy dressed as Garnet (pre-Jail Break outfit) standing tall and confidently with her legs apart and her arms lifted both sides of her in a powerful stance with Garnet's gauntlets. Her ears are sticking out from her Afro. On the right side of the painting is Skeeter as Amethyst in her original pre-Reformed outfit. She looks like she's just running into the picture with a big smile on her face and holding the handle of her whip above her head as if she's about to crack it. On the left side is Janice as Pearl, post-Steven the Sword Fighter outfit. She stands in a graceful stance, holding her spear upright with her right hand and her left leg extended out like a ballerina. She's smiling down at Robin as Steven, who's in mid-jump in the air excited between Janice/Pearl and Piggy/Garnet. He's wearing the same as Steven (even is dark curly hair) except for the sandels.