A new leak suggests that a Compact variant may launch alongside the Sony Xperia XZ4. However, if this pans out, it could be a slightly disappointing release, especially next to the full-size version. The phone portrayed in the rumors has a distinctly outmoded display design, a single rear camera and a design that does not vary much from previous years.
https://www.notebookcheck.net/Sony-Xperia-XZ4-Compact-also-in-the-works-new-leak.376191.0.html