I would use a separate CB Project for the mediainfo and libmediainfo.
I would use a normal CB Project for mediainfo
And, a custom makefile cb project for libmediainfo.
The reason to use makefile cb project for libmediainfo is because there is a CMake folder for the library.
I would work on building libmediainfo first.
CMake can be used to create a custom makefile cb project.
I would try converting one of the Visual Studio projects into a normal CB project using the import tool for mediainfo project.
I use external dependency option in CB for dependency management; I have never had good results from using CB Workspace/project dependency.
Edit: If you are trying to cross compile this project; I would not try doing that myself; it is not easy to cross compile any project that was created without cross compile support!
Tim S.