A new WoW book listing has been found on Amazon: The Dragonflight Codex. This book is likely the Dragonflight counterpart of the Grimoire of the Shadowlands. The book description also talks about one major character being a Bronze Dragon all along.
Amazon listing for the Dragonflight Codex
It is uncertain if this is actually an official listing from Blizzard or not, as they haven’t announced the book themselves, so take this information with a grain of salt for now.