The Xperia line may be a getting a refresh in the form of the Xperia XZ2 Compact if a photo posted on Xperia Blog is to be believed. The photo, which was posted by a commenter, claims to show off a prototype of the small form factor flagship rumored to appear at MWC 2018 next week.
https://www.notebookcheck.net/Leaked-photo-shows-possible-prototype-of-Sony-Xperia-XZ2-Compact.284878.0.html