The YoRHa Edition is distinguished by its retrieval of "Ghost Data"—optional simulations and cosmetic modifications that offer a glimpse into the absurdity of the machine consciousness.
The original 2017 Steam version of Nier had a bug where resolution scaling was broken. If you set it to 4K, it often rendered at 900p and upscaled. The YoRHa Edition (legit) fixed this, and the CODEX version inherited that fix. Furthermore, while the legit version requires Steam to be running (even in offline mode), the CODEX version is completely standalone. nier automata game yorha edition codex