If "God of Lies" by Sasha Leone interests you, consider checking:

While Amazon uses its own format (AZW3/KFX), you can easily purchase the Kindle version and use free tools like to convert it to EPUB or PDF for non-Kindle devices. Amazon frequently runs promotions, and Kindle Unlimited subscribers can often read the book for free as part of their membership.

God of Lies (Soulless Empire, #3) by Sasha Leone | Goodreads

Sasha Leone may also distribute through Smashwords, which offers every format imaginable: EPUB, PDF, MOBI, RTF, and even plain text. This is the ultimate destination if you absolutely need a specific file type.