When configuring WL HTTP Adapters, the domain and port are part of the adapter configuration .xml file build and uploaded on the WL server. For our use case (especially beta
You can´t. An option is to use MashUps.
See:
IBM Worklight 6.1 - Can a HTTP adapter call another HTTP adapter on server-side?
http://public.dhe.ibm.com/software/mobile-solutions/worklight/docs/v620/04_11_Advanced_adapter_usage_and_mashup.pdf
The idea is to have an Adapter responding to app mobile than this adapter call other deployed adapter (QA, Test Env, Prod Env, etc) considering any logic.