Apparently, the name Libelle means “dragonfly” from a German origin. But “libelle” is translated as a diminutive from liber “book” from Latin libellus. So I guess they chose it partly because of the Latin meaning and it sounding like “libel,” as you said.
Is she called Libelle, because it is similar to libel? You know, slander but published/written down? Cause that's cute and smart hahahhaha