Once turtles lay eggs, they have no further involvement with the nest, so in that sense there would be no harm in relocating them. However, they do have home ranges with which they are familiar, and transporting them, or any other animals, to unfamiliar areas can be a virtual death sentence. Animals depend on known sources of food and shelter, and we are usually not qualified to determine what is and isn't suitable habitat for them. If you find a turtle on a road, the best approach is simply to ferry it across the road in the direction it's going and let it continue on its way.