Yes, you can do that if those namespaces aren't dependent on other code in the project.
Just create a new project with those namespaces and make sure that it compiles fine. Then right click it and select Properties, select Android, tick the Is Library check box.
After that import this project into your current workspace. Right click on your main project, Properties, and go to Android. Click on Add and add the library project. (But don't click on Is Library this time).
For more understanding you can see how we use AndEngineGles2 in our projects to create 2D games in Android.