The $\mathrm{\Gamma }$-point topology represents a significant segment in the family of topological insulators. Here we provide a comprehensive prediction of light-induced $\mathrm{\Gamma }$-point-based topological manipulation in trigonal bismuthene and its derivatives. Our findings unveil a two-stage process of topological phase transitions (TPT) as the laser intensity increases. Initially, a quantum-spin-Hall or metallic state transitions to a quantum-anomalous-Hall (QAH) state ($C=\pm 3$), followed by another TPT that yields a compensated Chern-insulating state ($C=0$). The trigonal warping model accounts for these states, describing the $C_{3z}$-rotational band-inversion process, which is determined by $\pm 1$ orders of replica bands. Notably, this high Chern-number QAH state persists over a broad range of laser parameters. It remains functional beyond room temperature, as indicated by the substantial global energy gaps ($\ge 60\mathrm{meV}$) that are less constrained by other factors, including magnetic transition temperatures and doping effects. Our work provides a comprehensive roadmap towards the designer $\mathrm{\Gamma }$-point topology under laser excitation, facilitating applications of artificial topological materials.

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• Photoinduced effect
• Quantum anomalous Hall effect
• Topological insulators
• Topological phase transition