Currently you can only use Switch action on text. But it would be nice to be able to switch on application. Without switch, you are forced to use ifs inside ifs and it's not as nice.
Not sure how edifying this example is, but FWIW one can also switch, in a JS action, on the bundleIdentifier of the front application, and then delegate to a specific macro whose name is simply that identifier:
The Copy front document as Markdown link in this KM group calls whichever macro (if any) has a name that matches the bundle identifier of the active app: