The command
causes function keypresses while in talk mode to be sent intact and
untranslated to the remote system. The remote system will then act
on that function keypress in its usual way. The command
causes function keypresses while in talk mode to be translated locally and the results of the translation to be sent to the remote system. fkey local is the default fkey setting.
fkey affects function key translation only while you are in talk mode (talking to the remote computer). Regardless of the fkey setting, function keys will always be translated by your local computer when you are in command mode (talking to your local Autolog program).
Your local function keys may not generate the characters that the remote system expects to see. For example, if your F1 key generates the escape sequence ESC O P but the remote system expects ESC Q, you may need to use the key command to change the character(s) generated by your function keys while in talk mode.