The installers contain 2 (two) different products, a) the Performer desktop app and b) the plugin set for Cubase or Nuendo. Thus, the latter replaces the versions that were installed with Cubase.
Only the PRO version of the plugin allows for local connection with the Performer app (either desktop or iPad). No local connection is possible with Studio Pass.
A local connection is one using the same network. An example of a non-local connection would be if one device is connected to the internet via WLAN (WiFi) and the other via 5G. So if your Cubase VST Connect is connected to your home network, you might switch off WiFi on your iPhone so that it connects to 5G (or any other such network) and run Studio Pass there. Unless you have a flatrate with your phone network provider, this will introduce cost or eat your quota though.
Does that answer your questions?