I am quite new to the jack audio software.
I was wondering, whether it is possible to specific applications to specific outputs.
I know could make a virtual device that I can connect anyway I want. But that only works if I am able to select the virtual device as output device within the application, right?
But not all applications have the option to chose outputs.
So the question is whether I can select an application in jack audio and route it the a device of my choice.
Being able to do this is the main reason why Jack exists. You can connect anything to anything with an external patch bay, you don't need to use the UI of the application.
Examples of graphical patch bays you can use are (my) Patchage, Catia, and qjackctl. You can also use jack_connect on the command line.