Unraveling the mechanisms of ergodicity breaking in complex quantum systems is a central pursuit in nonequilibrium physics. In this work, we investigate a one-dimensional spin-1 model featuring a tunable long-range hopping term, $H_n$, which introduces nonlocal interactions and bridges the gap between Hermitian and non-Hermitian regimes. Through a systematic analysis of level-spacing statistics and Krylov complexity, we demonstrate that $H_n$ acts as a universal control parameter driving the transition from integrability to quantum chaos. Specifically, increasing the strength of $H_n$ induces a crossover from Poissonian to Gaussian orthogonal ensemble statistics in the Hermitian limit and similarly triggers chaotic dynamics in the non-Hermitian case. Most remarkably, despite the onset of global chaos, we identify a tower of exact nonthermal eigenstates that evade thermalization. These states survive as robust quantum many-body scars, retaining low entanglement and coherent dynamics even under strong non-Hermitian perturbations. Our findings reveal a universal mechanism by which long-range and non-Hermitian effects reshape quantum ergodicity, offering pathways for preserving quantum coherence in complex many-body systems.

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• Quantum information processing
• Quantum scars
• Spin dynamics
• Non-Hermitian systems
• Quantum spin chains