No, the installation of the device does not require the skills of a plumber or an electrician. The devices are attached to the respective main supply lines (electricity, water) but they are not connected to them.
Swiss Harmony devices act through resonance. So neither the water nor electricity must flow through the devices. They must just flow past them.
Nevertheless, there are certain things to consider to ensure a correct positioning.
More information on the technical background of Swiss Harmony can be found here.