Achieving purely electrical manipulation of valley degrees of freedom, independent of magnetic fields, represents a critical milestone for next-generation nonvolatile electronics. Using first-principles calculations, we establish bilayer ${\mathrm{CuCrP}}_2{\mathrm{S}}_6$ as a robust platform for such control, driven by the interplay between ferroelectricity and antiferromagnetism. In the ferroelectric state, broken inversion symmetry and spin-orbit coupling induce a single-spin valley-polarized state with a 20.34 meV splitting, enabling an anomalous valley Hall effect where carrier spin is locked to polarization. Conversely, the antiferroelectric state restores effective parity-time symmetry, suppressing macroscopic splitting. However, we uncover a nontrivial hidden Berry curvature in this regime that generates a layer Hall effect characterized by layer-contrasting spin currents. Our findings demonstrate that electrically toggling between ferroelectric and antiferroelectric orders reversibly switches the system between a spin-polarized valley transport regime and layer-selective transport, facilitating valleytronic logic operations without external magnetic fields.

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• Electric polarization
• Ferroelectricity
• Magnetic coupling
• Spin-orbit coupling
• Valleytronics
• 2-dimensional systems
• First-principles calculations