The Internet is still recovering from the bombshell that is Bowsette - the theoretical fanservice-laden version of Bowser that is created when he dons the Super Crown from New Super Mario Bros. Deluxe U.
The sheer popularity of Bowsette has led to some fans wondering if she will appear in some form in a future Nintendo game. If she does, then her outfit will certainly be more conservative than what is she wearing in most of the fanart drawings, but it would still be nice for her to be canon.
It turns out that Bowsette was almost canon, as unused concept art for Super Mario Odyssey has revealed that a reverse of the Super Crown + Bowser = Bowsette situation almost happened in the game.
The Art of Super Mario Odyssey is a book that is filled with concept art from the game, some of which from ideas that went unused.
A user on Twitter named Daisuke Kihara has uploaded a comic page from The Art of Super Mario Odyssey which reveals the unused plans for what almost became the original Bowsette
マリオデ資料集を拝見。ううむ、これは充実のアドベンチャーブック……そして没案とはいえ、まさかのクッパピーチが登場。— 木原大輔（ゲーム文芸編集者） (@d_d_kihara) September 28, 2018
One of the original ideas for Super Mario Odyssey involved Bowser owning a cap that could possess people, which was essentially an evil version of Cappy.
At one point in the game, Bowser would use his cap to possess Princess Peach, creating a sort of reverse Bowsette, where Bowser's cap takes over Princess Peach's body, giving her a green dress, bright red hair, red eyes, yellowish skin, Bowser's spiked bracelets, and a tail.
In the final version of the game, Bowser doesn't possess a magical Bonneter (which is the name of Cappy's race), although Mario does possess Bowser at one point near the end of the game, allowing you to use his strength to survive in one of the final levels.
It's almost eerie seeing how similar the concept of Peach being possessed by Bowser was to Bowsette. Nintendo almost struck gold with a character design that has been adored by people all over the world, yet they decided to scrap it.
This just goes to show that sometimes the best ideas are left on the cutting room floor.