Basically any Android phone where you can gain root access is capable, you can set up automatic recording of every call and set answering call with a button (like Volume Up).
Don't know about FP3 specifically, but on some phones it's built-in in accessibility settings (all Samsung phones for example). For other phones you can try an app such as Button Mapper and assign "accept call" to a button.
Are you sure? I didn't find that option on FP3.