We report on double-quantum dot (QD) molecules realized with modulated quantum wire (QWR) heterostructures by self-limiting growth of AlGaAs alloys in inverted tetrahedral pyramids. The QWR barriers connecting the dots facilitate the tunnel-coupling between the confined carriers. Evidences for the presence of such coupling are provided by conventional micro-photoluminescence measurements and theoretical modeling. Systematically tuning the relative QD sizes in the QD molecules reveals spectral line splitting consistent with the expected level splitting due to carrier hybridization. Prospects for extension of these structures to larger QD superlattices are discussed.