The altermagnetic spin-splitter effect converts an electric field into a transverse pure spin current, with no net magnetization and no charge-Hall counterpart. In established materials this function is tied to crystal-fixed spin-split bands that lock the polarization axis to the lattice. We show that the noncoplanar counter-spiral ground state of a frustrated honeycomb magnet instead carries the altermagnetic operation through a Q-locked helicity mirror g. The mirror selects the spin-current polarization and forbids the perpendicular one, while an antitranslation Θ forbids even-parity spin splitting. Band splitting and spin-splitter response therefore rest on different symmetry elements. Either element alone enforces the charge-Hall zero—a redundancy absent from other spin–orbit-free noncollinear routes—and a charge Hall appears only when both elements are removed. Hole doping then realizes a spin splitter without spin-split bands—the symmetry-allowed odd-parity residual below 2×10⁻⁷ of the hopping t at the Fermi level—with σ_H^((s_y))=0.082 e²/h without spin–orbit coupling and with zero charge Hall response. Selecting among the three degenerate Q orientations rotates the polarization axis in exact 120^∘ steps at fixed magnitude and charge-Hall zero; the selection rules persist in a 32-site cell accessible to programmable photonic and circuit lattices.