E4321 error

Two dependencies in one addon's graph bring a package of the same name from different sources, for example one from git and one from a path, or the same repository at two URLs. A package is identified by its name and its source, and an addon can only embed one copy of each package.

Make every package that depends on it use the same source. The notes say which dependency uses which source. The error comes from dependency resolution, so it has no example here.