Generally speaking this will work, yes! Plants use more water during active photosynthesis, and unsurprisingly, water evaporates faster in the open sun.
But logistically, on-demand shading of whole fields is quite challenging. And not all crops will be robust to being grown in the shade (for varying levels of shade).
But logistically, on-demand shading of whole fields is quite challenging. And not all crops will be robust to being grown in the shade (for varying levels of shade).