"deep-diver" or "shallow-diver". Plugs can also be designed to hover (neutral buoyancy), sink slowly, or sink rapidly. Some have a small metal ball inside to "rattle" when retrieved.
There are two types of plugs: those that dive deeply and those that only reach shallowly. Additionally, some plugs can be made to hover, sink slowly, or sink rapidly. A few have a small metal ball inside to create a rattling sound when they're brought back up.