The optical control of spin- and valley-selective gapless states in two-dimensional materials presents new opportunities for next-generation spintronic and valleytronic technologies. In this work, we study monolayer jacutingaite (${\mathrm{Pt}}_2{\mathrm{HgSe}}_3$), a quantum spin Hall insulator with strong intrinsic spin-orbit coupling, under irradiation by circularly polarized light. The light-induced Floquet engineering gives rise to tunable topological phases, including transitions to spin- and valley-polarized semimetallic states. We probe the topological transitions using spin and orbital Edelstein effects—nonequilibrium responses from spin-orbit coupling in noncentrosymmetric systems. While not a full substitute for Chern invariants, sharp changes in these responses, such as a discontinuity in spin Edelstein conductivity and vanishing orbital susceptibility, signal the onset of the semimetallic regime. Furthermore, we investigate how the growth and suppression of the spin Edelstein responses across the topological phase transition depend on the interband scattering time. These findings establish the Edelstein effect as a sensitive and experimentally accessible probe of light-induced topological transitions in quantum materials.

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• Light-matter interaction
• Quantum spin Hall effect
• Spin-orbit coupling
• Topological phase transition
• Dirac semimetal
• Floquet systems
• Bloch-Floquet theorem
• Linear response theory