My Webcore piston was based off of a hacked driveway alarm. I connected a contact sensor to the alarm so that when someone entered the driveway triggering the alarm, the contact was closed (temporarily) which triggered the piston. It would raise the outdoor lights to 100% for 10 minutes and then return them back to 5% dim.
I have something similar set up. Adjust your two lights to the 5% setting and capture it as a scene. Then create a rule to activate the scene at sunset and turn off the lights at sunrise. Create another rule to turn on the lights 100% when the switches are turned "on", activate the scene when they are turned "off" after sunset, and turn them completely off after sunrise. Perhaps LOMP is simpler, but this works as well.