Module usage questions - Field matching capabilities

Hello, I would like to ask a couple of questions with regard to the functionality of this module.

I was considering using the built-in support for filtering entities reference options through a view, but it appears to be work in progress.

I also thought of the Entity Reference Views Widget, but apparently supporting reference fields with cardinality = 1 is not implemented yet.

It is my understanding that this module matches values on fields.

• Does it have to be the same field (reuse existing field) or can it be fields of the same type?
• Does this module cope with fields of the same type (e.g. references) but with different cardinality?

My use case is as follows:

Certain Products are sold at Events. An Order for such an Event needs to present the user with only the Products that are sold at that Event and not all Products system wide. I initially did not have any back-references from the Product to the Event, but I guess if I don't it will be hard to get a match.

Problem is that an Order will reference only one Event (definitely) and Products will reference multiple Events (possibly). Will this module match on fields where the type is the same (entity reference to Event), but the cardinality is different? i.e. show a Product in the Order as an option, only if the Product has at least one reference to the same Event that the Order uniquely references.

Thank you