https://www.techradar.com/news/moto-z3-play-design-specs-and-bundle-details-unearthed-by-leak

The Moto Z3 Play should be in for a slight redesign, if recently leaked documents are to be believed. 

Compared to its predecessor, the Moto Z2 Play, this one is said to be going under the knife to shift its fingerprint sensor around to clear the way for minimal bezels. But due to the nature of the company’s Moto Mods, which snap onto the phone’s back, it’s reportedly integrating the biometric feature into the side-mounted power button.