This study presents an integrated experimental and numerical framework for the mechanical and piezoresistive characterization of plate lattices fabricated via filament deposition modeling. Material-level tensile and compressive tests are conducted on polylactic acid doped with carbon nanotubes, considering multiple printing orientations. The results reveal pronounced print-induced anisotropy (up to 70% variation in tensile strength), tension–compression asymmetry, and direction-dependent sensing behavior. Body-centered cubic (BCC) and face-centered cubic (FCC) plate lattices with varying relative densities and printing directions are fabricated and tested under compression. The FCC lattices achieve a maximum strength of 11.8 MPa, while BCC lattices reach a stiffness of 588 MPa. A constitutive model is calibrated using the material-level data: elastic behavior is described with a reduced transversely isotropic formulation, and inelastic behavior is captured using either the Hill anisotropic yield criterion or Drucker–Prager plasticity. Piezoresistive response is modeled linearly, assuming operation within a non-damaging loading regime. Model calibration is performed through closed-loop optimization across all printing orientations and loading cases. The calibrated models are validated against BCC lattice experiments, showing excellent agreement. This framework provides not only global material models but also a robust foundation for the design and characterization of multifunctional lattice materials.