Battery-% is changing. 
No sim card and no mobile connection.
No bt and wifi.
May freeze after while. Vol up + power switch pressing help to cut off.
C:\Users\xxxx\Downloads\0212_20092024 X 10 V>fastboot flash oem_a SW_binaries_for_Xperia_Android_14_5.4_v5a_zambezi.img
Sending ‘oem_a’ (422329 KB) OKAY [ 10.438s]
Writing ‘oem_a’ OKAY [ 0.000s]
Finished. Total time: 10.673s