Yes, you heard it right, it's possible to enable fingerprint scanner on the devices. There's a software trick involved: all you have to do is to flash the unit to a different region (say, the UK).
For example, the first screenshot below is of a US Xperia XZ (with the customization number: 1304-9026), while the right one was taken after the unit was flashed with UK firmware (note that the customization number has changed).
Once the above mentioned step is done, you'll observe that the feature is now enabled on your phone.
Keep in mind, however, that the process may void your device's warranty. For more details on how to enable the fingerprint scanning feature, head to the Via link below.