At night, have the pool water pumped
through a large sprinkler-type thing
that sprays it above the pool and lets it drift back down.
The evaporative properties will cool the water
below ambient with very little energy involved.
It wouldn't make a huge difference but would help a little.
Installing a small "cooling tower" would be much more
effective and could be set up with natural draft or an
induced draft fan.
Here's an example of one, with a rating of 75,000 BTU/h
Could be overkill at a cost of $2,150.00 but could be
scaled down to meet the needs.
At 1/6th horsepower the electrical draw wouldn't be excessive
and if you have a variable speed pump you could set it on low,
or install a small circ pump just for the cooling tower.
https://www.portableairgroup.com/product/cool-it/water-cooled/model-t-25-75000-btu-h-5-ton-cooling-tower/https://www.portableairgroup.com/product/cool-it/water-cooled/model-t-25-75000-btu-h-5-ton-cooling-tower/