Micaiaha Johnson’s The Space Between Worlds, published 04 August, 2020.
There are 382 parallel Earths and Cara, the MC, is alive in 8 of them. These 8 are the Earths she should not traverse into, because no one knows what happens when you meet yourself in another universe. It’s probably as catastrophic as meeting yourself when time travelling. I digress.
Cara grew up in the wastelands, she thought she’d die young out there, like her mother, but one day she finds a way to use her risk-affine personality. She becomes a traverser, a person travelling between parallel universes. A job she can only do, because she died on most of the alternate Earths. One of the golden rules of traversing is, never to enter a world where you could meet your parallel-self. As any high-risk fiend, she has to break the golden rules: she meets an alternate self, she meddles in other-universe affairs, she discovers a conspiracy on her home base Earth 0, which she then has to try to stop.
Johnson created a wonderful world: the wastelands, ruled by a cruel warlord; the city full of multistory buildings, the different religious systems, and the traversing. Although the beginning of the novel is slightly confusing, because it takes some time to find out how traversing works, the pacing is excellent and it was very hard putting the book down.