I am currently running the Phosh image on the pinephone.
It is currently the one that works best for me.
I have been debugging pacman-mirrors on the phone because the --interactive did break - with a Gtk init failure.
I have not yet found the issue but I created a workaround - which launched the console UI if it is an arm device.
During that debug session I found that the locale.conf needed an extra entry - in my case
The current version of pacman-mirrors is now v4.19.1