$\mathrm{C}{\mathrm{o}}_x\mathrm{Ta}{\mathrm{S}}_2$ ($x\approx 1/3$) exhibits a spontaneous Hall effect from spin texture in antiferromagnets, with a tetrahedral triple-Q (3Q) order and uniform spin scalar chirality. Upon Co overdoping ($x>1/3$), it undergoes a shift in magnetic ordering vectors from ${\mathbf{Q}}_{\mathrm{m}}=$(1/2, 0, 0) to (1/3, 0, 0). Interestingly, the spontaneous Hall effect disappeared in the overdoped regime, which was originally attributed to the loss of 3Q order. However, a question remains whether a new type of 3Q order can exist with alternating chirality in the overdoped regime. To address this, we investigated $\mathrm{C}{\mathrm{o}}_{0.336}\mathrm{Ta}{\mathrm{S}}_2$ using inelastic neutron scattering (INS), neutron diffraction, and optical dichroism, and found that INS data and spin-wave simulations support a 3Q order with alternating chirality. Moreover, neutron diffraction data show field-independent Bragg peaks, while linear dichroism detects no in-plane anisotropy, consistent with threefold rotation symmetry. Our data support the scenario of an alternating-chirality 3Q order in $\mathrm{C}{\mathrm{o}}_{0.336}\mathrm{Ta}{\mathrm{S}}_2$, canceling the spontaneous Hall effect. This study highlights a combined neutron-optical approach to identify complex spin textures.

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• Magnetic order
• Magnetism
• Spin dynamics
• Spin texture
• Single crystal materials
• Landau-Lifschitz-Gilbert equation
• Linear spin wave theory
• Magnetization measurements
• Neutron scattering