There are various products around to deter cats from using certain areas as a litterbox. All in all though, if you really don’t want to deal with it, keep your cats indoors.
Cats are cats, they love to go in areas of soft soil, sand, etc. and the better the dig site, the better they like it.
My cat (s) one’s gone now have 5 acres to crap on, the world is literally their litter box, but, they prefer to go in my corral where I lay down a truckload of sand once or twice a year.
I just periodically rake out the poo.
Trying to get a cat to not behave like a cat is an exercise in futility.