The Sony Xperia XZ has its fingerprint sensor disabled in the United States
Since the Xperia Z5 line-up came about, Sony Mobile has had the curious policy of excluding fingerprint sensors from its flagship smartphones sold in America. However, an investigation by independent Android developers has revealed that Sony has merely disabled the fingerprint scanning functionality via software limitations, instead of going all-in and removing the physical components required for fingerprint reading.
Thus, re-enabling the fingerprint scanner on US devices such as the new Xperia XZ
and X Compact appears to be a question of changing the smartphone's region by flashing software from another country, such as the UK. Of course, this is also a process which voids your warranty, so there's a bit of compromise to consider.
You can still flash back the American software, though, which would restore the smartphone to a factory state. But losing your warranty is definitely something to be wary of if you are interested in modding the Xperia XZ. Should you decide to gamble, follow the instructions from this link
and treat yourself to the fingerprint scanner you should have received in the first place. Reportedly, the procedure is pretty straightforward, though we haven't tried it out for ourselves – thus, proceed at your own risk!