I am using extension library Rest controls ViewJsonservice to provide the data from Notes database, is there a easy way using same control I can provide the data from two databases, I can put the similar view from dbA to dbB
Short answer: no
Long answer: I presume you want the data from 2 views available in a single endpoint. Either after each other (appended) or somehow merged.
You can do that using code. Check this article for basic info.
In a nutshell: use the ViewNavigator class in both databases to retrieve results and append or merge the data before you return it.
Nice side effect : you can return all the data.