The android device identifies itself as device for ADB (Android Debug Bridge).
$ adb devices
List of devices attached
5727aa6d device
In my case LineageOS 20.0 test build the name contains whitespaces and can therefore not adressed from scrcpy.
$ adb devices
List of devices attached
CDC ACM Data device
Which property we can set to change the adb device name?
ro.boot.serialno
orro.serialno