Sony can update the name of their Xperia phones. It is said that Xperia XA3 and Plus actually called “Xperia 10” and “Xperia 10 Plus”. It’s more than that, the name “X” could completely disappear.
The Xperia XZ4 could be introduced under the name “Xperia 10Z”. Other letters are also possible – like “Xperia 10X” – but since X = 10 we think that the use of a “Z” makes more sense (besides, it reminds of old ones) of Xperia Z).
The “X” series appeared in 2016 for the first time before being divided into two categories: Premium XZ and Mid-range. As for the Xperia line itself, which debuted in late 2008 with the Xperia X1, the tenth anniversary took place a few months ago.
PS. Sony Japan teases purple as a possible new color for the Xperia XZ4 or 10Z, if that’s the name.