Finding nobody has already done this (?!?!), I made a kitsun.io deck for hiragana and katakana.
note that i used “ji” and “zu” for ぢ and づ.
i’m adding the yoon as we speak.
This is what I wish wanikani had as an optional level zero… anyway, I hope it’s useful to some of you. Please let me know if you see mistakes or things I left out.