It could be an imaginary language. There are certainly stranger examples, like the Codex Seraphinianus: https://www.openculture.com/2017/09/an-introduction-to-the-c...
It was part of early efforts to make learning Mormonism “easier” for immigrants.
The alphabet failed to take on. Original copies of what was printed are rare.
https://en.wikipedia.org/wiki/Deseret_alphabet
https://www.schilbantiquarian.com/product/1868-1ed-deseret-a...