Android Library Modules dependency

I have Library A and B with Mock and Prod Flavor.

Library flavor( Mock and Prod)

I want to add dependency in my Application Gradle for Instrument Testing using Espresso, which have 4-Flavor Mock-Beta-Staging-Prod. App Flavor( Mock, Beta, Staging, Prod)

How will i be able to do instrumentation testing using Mock flavor of my Library A and B?

what will be the gradle setting for release to take prod flavor of my Library Modules?