RobotStudio event

Create Author Components Library with multiple Mechanism variations

Hello everyone,
I would like to know is it (or how is it) possible to create a Library with multiple Mechanism variations where user can select desired option from predefined options (as when adding IRB120 Mechanism, where user can select which version to add from a dropdown: IRB 120;IRB 120T;IRB 120FGL)?
According to the LibraryCompilerSchema.xsd, it can be done using Variant tag under Library, but I can not make it work. Is there some kind of example how this tag can be used?
If this is not possible by the way proposed, is there any other way I can make it function like explained?