theoretically it should be possible, well you can edit the binds file in notepad++ or similar text editor
looks like ED would expect any function key press assigned in the binds file to be referenced as Key_F1 - Key_F12
A list of key and button values for use in .binds files in Elite: Dangerous - ljvasey/elite-bind-values
github.com
however it really depends how ED has been coded to read the binds file and would expect any F key beyond 12 will be iignored as the ED binds key value will need to be converted to keycode. if the key is recognisable you should be able to assign the key press by editing your key mapping ingame
if youve got a keyboard which has more than 12F keys there will usualy a macro or key-mapping editor provided by trhe manufacturer which will allow you to bind controlls to those additional keys
or you could try something like auto hotkey or voice attack to assign macros to those keys