Can Espresso work without launching activity with intent?

I want to write an Espresso test that will use currently launched activity on the tablet's screen. So I'll navigate to this activity with appropriate content manually prior launching the test, cause it's difficult and reluctant to write additional code to launch this activity with the same global "state" in app and pass all needed params in the launching intent and so one.

Is it possible and how to do this with Espresso, or I have to use UI Automator then?