Hi,
Currently, it's not possible, but I am working on an introspection system that will give you an overview of everything in an xml format so that you can then apply filter and search for this kind of data.
If you are interested, I have an alpha version that is likely suitable to find out this information as I go over all fsm and list eery fsm variable, their name and their type, so with a simply Xml Xpath query we can find out what fsm/GameObjects/scenes have these variables.
But, this won't work at runtime, it's only an editor tool. Is that ok?
Bye,
Jean