Indeed, that was also noted in Libraries showing twice in .pio/libdeps - #8 by maxgerhardt. Referencing a library via git will not change the fact that the library itself references a dependent library via a regular name and version in the library.json, so that will be pulled in from PlatformIO too, if the user additionally specifies a differing version of the library to be in the project, that too will be in there, thus you see it double.