the French novel by one of the Oulipo guys, that's 300 pages long and doesn't use any letter "e"s. I looked this up immediately because I had to know how the heck a Japanese translator would even carry over that concept, and it looks absolutely wild. The translation by Shiotsuka Shuichiro is titled 煙滅, "vanishing like smoke", and it doesn't use any kana with "i" sounds - no i, ki, gi, shi, ji, chi, ni, hi, bi, pi, mi, ri, or wi, including kanji containing those sounds. I really like that as a translation, it feels conceptually clean and seems like roughly the same level of difficulty - you lose a decent chunk of vocabulary, and there's certain verb and adjective conjugations that you mostly can't use directly, but it doesn't seem impossible to write under that constraint with a few contortions. I ended up ordering a copy because I'm super curious what that looks like in practice.
I also found an Asahi Shimbun book review by Okuizumi Hikaru, an author with some fascinating takes (the review is in Japanese, this is my translation):
[...] To ask, what's the point of doing this? is the same as asking what the point is of reading or writing novels at all. Doing these sorts of tricks is fundamental to what novels are. To put it plainly, a novel is art made with words; those who don't understand the point of this may not be looking for a novel at all, but rather a comforting narrative, or a good story. Obviously, most novels are also "narratives". However, taking a narrative pre-formed in one's mind and precisely laying it out in words is not a novel. Rather, the way words transform and produce the narrative is what makes a novel a novel. In that sense, there is nothing at all paradoxical in saying that this work, where the absence of a particular letter controls and guides the course of a mystery-style narrative, is one of the most novel-like novels there is.