mosfet as freewheel diode
The diode should be placed as close to the MOSFET as possible. You need to protect the MOSFET from spikes, which would be produced by the wiring inductance, if the diode was placed far from the MOSFET.
The extra inductance that is added by the wire simply adds to the motor inductance, so from this point of view, it does not matter (it matters for EMI to keep the connections short). Although the wire inductance can be significant to cause large spikes to make the MOSFET fail, it will be negligible compared with that of the motor.
But even if it was not negligible compared to the inductance of the motor, it would not produce any negative results, to the contrary: the larger inductance would cause lower current ripple. In fact, sometimes an extra inductor is added in series with the motor, in order to reduce the current ripple, especially if the motor has a very low inductance.
This arrangement suggests right away that the diode should be placed close to the MOSFET.