Views - Exposed Filter for 2 Field Collections with Same Fields
You need to make the base table for your View the Field Collection table rather than the Node (content) table.  You'll need to add a filter to only show the type(s) of Field Collections you wish to query.

Now you'll be querying all Field Collections of the selected type(s), regardless of whether they're considered authors or editors.  Simply add exposed filters to query on the first_name and last_name fields.

The real question is: what do you want actually displayed?  If you only want data attached to the Field Collections displayed then that's easy enough.  If you want to pull data from the host nodes beyond merely the NID then you're going to end up with 2 separate relationships to the nodes (one for each field) and you're probably not going to be able to get the UI you want out of that.  

A much easier approach to all of this would be to put all of the "people" related to a node in a single Field Collection field and differentiate between Author and Editor by way of an additional "type" field in the Field Collection.  You could then construct very straightforward views to query across all types of related people.