No, you cannot. With 8.0 SP1, the Pega Native Foundation product was introduced into the application. This software is installed within the same folder as Studio (or Plugin, or Runtime) and so you cannot have all variations of the product installed because there is only one Pega Native Foundation. If you try running another variation... you are ultimately missing a key component of the application.
In reality, you should never need to install more than one variation. Pega Robotics Studio comes packaged with both the full Runtime product along with Studio.