Two-dimensional (2D) semiconductors possessing strong spin-orbit coupling (SOC) and nontrivial topological features are central to the development of energy-efficient spintronics. While Weyl physics is extensively studied in semimetals, its realization in atomically thin semiconductors remains limited. Using first-principles calculations, we identify layered ${\mathrm{SnP}}_2{\mathrm{Se}}_6$ as a versatile topological semiconductor platform. In its monolayer form, the intrinsic structural chirality gives rise to a coexistence of Ising-type and Weyl-like (the properties of this material cannot be fully characterized as those of Dirac or Weyl materials) SOC. The latter is characterized by radial hedgehoglike spin textures—a signature of unique manifestation of Weyl-type SOC in a 2D chiral lattice within a 2D semiconductor—resulting in a significant intrinsic spin Hall conductivity (SHC) of up to 10.2 (ℏ/e) S/cm. In multilayer ${\mathrm{SnP}}_2{\mathrm{Se}}_6$, symmetry evolution facilitates a distinct regime where Weyl-like and Rashba spin textures coexist. This transition preserves substantial spin-charge conversion efficiency while introducing chirality-switchable components to the SHC tensor, providing a layer-dependent degree of freedom for spin manipulation. The interplay between strong SOC, topological band features, and structural chirality establishes ${\mathrm{SnP}}_2{\mathrm{Se}}_6$ as a platform for thickness-engineered spintronic devices.

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• Chirality
• Electronic structure
• Spin Hall effect
• Spin texture
• Spin-orbit coupling
• 2-dimensional systems
• First-principles calculations
• Wannier function methods