Depending on Exoplayer modules locally

Studio is recognizing them as modules and they are added to your project. That window lists modules included in your project in the pane on the left that has all of the module names. The right side is for modules included in your project that are not pre-compiled and allow you to change things such as the build tools used when packaging the module bundled in your project. For those modules you would get a small bar graph looking icon where that blue square icon is on your exoplayer modules. The blue square means it is a pre-compiled and packaged module that you have imported into your project. Remember to include the modules you are using as a dependency on any package using them in the project and you should be able to import and implement their class members in any class of the dependent package.

If you click that plus + at the top of the left pane, it will allow you to add more local modules or search the repos in your project level build.gradle for more. Likewise, if you have a module name selected in that pane and click the minus - at the top, it will remove that module from your project as that is a list of the ones already added.

To make sure your package is depending on them, click Dependencies in the navigation pane of that project structure window in your screenshots. Then click the name of your package in the left pane, and use the plus + icon in the right 'details' pane of that view to select which modules in your project that package depends on.