One thought that immediately popped into my head was to skip the front page of the major app stores entirely and just dig into the publisher-specific imprints. Places like Fantagraphics or Drawn & Quarterly have built their entire identity on curating work with distinct visual voices. I found a novel, 'Monstress', honestly more for the art at first—Sana Takeda’s steampunk-meets-art-nouveau panels are unlike anything else in the mainstream.
You might stumble across something incredible just by following artists you like on social media instead of searching for novels. I discovered 'The Many Deaths of Laila Starr' because Ramon K. Perez posted some process art, and the whole book has this lush, vibrant watercolor texture that defines the mood. Algorithmic recommendations on big platforms tend to flatten style into genres, so you have to hunt a little differently for the truly unique stuff.
Sometimes a unique style isn't about being pretty, but about raw expression—like the chaotic, scribbly lines in 'I Want to Be a Wall' which perfectly mirror the protagonist's internal awkwardness. Those finds feel more personal.