Looking at FD indications at the gate (airspeed zero) on aircraft like the B744, it does seem that directions are based on mode. E.g. In FLCH with an altitude dialled in which is greater than the current altitude, the FD bar will go down (in an attempt to gain airspeed). In V/S mode, I recall that the FD bar went up.
Unfortunately, not all modes can be selected on the ground (e.g. VNAV)... and, of course, I am talking about an older generation (non-FBW) aircraft.