Likely related to Eugenia or Virginia-type forms, often carrying senses of 'well-born' or feminine refinement.
Gennia is probably related to forms like Eugenia or Virginia, which often carry associations of being well-born, refined, or feminine in a classical sense. That ancestry gives the name a faintly aristocratic air, even though the exact route into modern use may be indirect.
It feels like a name that has been shortened, softened, and refined through several stages of usage. As a modern given name, Gennia sounds light, graceful, and somewhat vintage. It has the pleasant ambiguity of a form that could be either a nickname or a full name, which adds to its charm.
The sound is polished without being stiff, and it hints at older European naming patterns while remaining approachable. Gennia fits the kind of naming that values softness, elegance, and a touch of old-fashioned distinction without sounding antique.