Washio Sumi wa Yuusha de Aru (aka Yuki Yuna)
Washio Sumi is a novel written in 2014 by Takahiro (Akame ga Kill, Majikoi, Tsuyokiss) and illustrated by BUNBUN (Sword Art Online). It was followed by more novels, all which tie into the Yuki Yuna anime franchise. The story is a hybrid of CGDCT and magical girl, with drama on the darker side. The anime is currently on its 3rd season, while the novels have yet to be published in English.
@cid I'd really like this one, been a huge fan of the series, but I'll be serious, I'd only buy it for collection purposes in a physical format. The novel was translated long ago already, and being 1 volume only, the anime already adapts its whole story. It'd be really hard to sell this one.
Despite also having a full translation, NoWaYu has a better chance of selling well, given that it has no anime adaptation.
Then again, they are so short that the risk might be mitigated enough. But that never got a license for that Angel Beats single volume prequel, so I wouldn't put much hope on it.