Hello
My FP2 always hangs during the initial setup wizard, not always at the same page, I cannot reach the end.
I tried a fresh install twice, with the TWRP version suggested in the docs. ADB sideload seems to complete successfully, however TWRP warns that there is no OS installed. After a reboot /e/ starts and later it hangs in the wizard and I have to remove the battery to shut it down.
This has been observed as a possible false alarm in TWRP on the Fairphone 2 for years, so as long as the OS boots afterwards … TWRP simply was wrong and everything else is up to the OS.
I don’t know why the initial setup would hang, though.
I think I would try to format the data partition and see whether that does something. In TWRP: Wipe - Format Data.
Keeping the power button pressed for about 15 seconds should force a reboot.
The last sentence should be written in the documentation page