As shutter speed affects the coming light on sensor.But has it any affect on movement of subjects in video?
Two things
The video gets brighter
The lower the shutter speed means more motion blur which makes it look more natural for the viewer
A high shutter speed can make individual frames look more crisp but make large motion look like it is stuttering. e.g. fast panning looks like it is flickering or jumping
A low shutter speed can make individual frames look blurred and make the motion look smooth.
A simple rule of thumb is to set shutter speed to double (x2) your project framerate.
EG: PAL project 25fps / Choose 50 shutter speed