Yes. Users are not limited to the content included in Anima.
Using the Anima Designer standalone application in Edit mode, it is easy to import and use 3rd party Posed (static) and Rigged (animable) characters, including motion capture data.
You will find more information about the import process in the following documentation:
- Import Custom Posed models (Static)
- Import Custom Rigged models (Animable)
- Import Custom Motion Clips (Animations)