Elastic Spacetime Theory (EST) models spacetime as a physical elastic medium whose voidstructure contributes a dynamical negative pressure at cosmological scales. In this work weidentify two sharp, falsifiable observational signatures that arise generically in EST cosmologyand are absent in ΛCDM: (i) a coherent void lattice with a characteristic scale of 110±5 Mpc,and (ii) a repulsive weak lensing signal inside deep cosmic voids with convergence κ ' −0.03.We further argue that the large-angle CMB anomalies commonly referred to as the “Axis ofEvil” may represent a residual imprint of an early-time two-dimensional elastic ordering transi-tioning into three-dimensional expansion. These predictions are directly testable with existingand forthcoming Euclid and LSST data, providing a near-term opportunity to confirm or falsifythe elastic spacetime paradigm. Author website: https://est-framework.org