Wirecast records and Replays what is in the Live Broadcast Area.
You can create as many ISO recordings as your system can support.
In previous versions of Wirecast you could create ISOs for each camera source. That's been the case for several years.
In Wirecast 14.1 you can now ISO Shots, not just cameras. The Shots don't have to be in the Live Broadcast Area but neither did the cameras previously.