Given the potential availability, non-toxicity, and environmental acceptability of alternatives to lithium-ion batteries (LIBs), secondary batteries utilizing magnesium (Mg) ions have garnered significant attention. Numerous recent studies have focused on identifying suitable anode materials for post-lithium-ion batteries, particularly magnesium-ion batteries. In this regard, we carried out a theoretical study to investigate the 2D multiphase molybdenum disulphide (1T/2H MoS₂) anode material using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Our observations confirmed the efficacy of this material as an anode. The results highlight its exceptional stability, high binding energy, enhanced metallic characteristics following Mg adsorption, theoretical specific capacity, and remarkably low diffusion barriers. Notably, the anode material exhibits an ultralow energy barrier of 0.04 eV, surpassing that of extensively studied 2D materials. By employing a wide range of Mg²⁺ concentration during the charging process, we achieved a high specific capacity of 4496.77 mAh g⁻¹ ions, coupled with an average operating voltage of 0.04 V. These findings provide valuable insights for the experimental design of exceptional anode materials.