Hi all,
Fairphone support replied by explaining that Google Phone app decided not to make available that feature in some countries. Apparently, but this is only my opinion, this decision is not related to legal issues as in Italy recording a call is perfectly legal.
However, a list of countries where call recording is available through Google Phone app (as a preinstalled application) is available at the link below:
https://support.google.com/phoneapp/thread/117420889/call-recording-availability?hl=en
As far as I have understood, in Italy recording a call on an Android device is only possible on devices that have a preinstalled phone application that allows accessing that feature.
Ciao,
Max