It really does depend on the species and how much the nest is moved. Some people have had success relocating the nests of Carolina Wrens, which are notorious for nesting in awkward places like door frames, downspouts. Some nests can be moved a little bit at a time. Sometimes when a nestling falls out of a nest in a tree, a person can make a temporary nest out of a container and put that in a raised location, where the parents can locate the nestling and continue to care for it. Human scent does not generally deter birds, very few of which have highly developed olfactory systems (Turkey Vultures being a notable exception).