Ferrovalley materials are a promising option for achieving controllable valleytronic and topological states in van der Waals heterostructures (vdWHs). Through first-principles calculations, we demonstrate that a type-III ${\mathrm{MoTe}}_2/{\mathrm{Cr}}_2{\mathrm{S}}_3$ vdWH can host multiple magnetically tunable topological phases. The broken-gap band alignment promotes charge transfer between the ${\mathrm{Cr}}_2{\mathrm{S}}_3$ and ${\mathrm{MoTe}}_2$ layers. However, charge transfer occurs preferentially between valleys with the same spin polarization, resulting in spin-selective band inversion and gap opening. The resulting topological phase is governed by the magnetization direction. With out-of-plane magnetization, a gap primarily opens at a single $K$ or $K^{\prime }$ valley, producing a valley-polarized quantum anomalous Hall state with one chiral edge state. In contrast, in-plane magnetization opens gaps at both $K$ and $K^{\prime }$ valleys, producing counterpropagating edge states that are characteristic of a time-reversal-symmetry-broken valley-polarized quantum spin Hall state. Furthermore, altering the stacking configuration and reversing the magnetization direction enables control over the sign of the Berry curvature and the activation or suppression of topological band inversion at the two valleys. These findings establish type-III ferrovalley vdWHs as a versatile platform for engineering spin-selective anomalous Hall responses and tunable topological valley transport.

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• Electronic structure
• Valleytronics
• 2-dimensional systems
• First-principles calculations