The electrocatalytic nitrogen reduction reaction (e-NRR) is a promising alternative method for the Haber–Bosch process. However, it still faces many challenges in searching for high activity, stability, and selectivity catalysts and ascertaining the catalytic mechanism with complete insight. Here, a series of graphene-based N-bridged dual-atom catalysts (M1-N-M2/NC) are systematically investigated via first-principle calculation and a high-throughput screening strategy. The result unveils that N₂ adsorption on M1-N-M2/NC in bridge-on adsorption mode can effectively break the scaling relationship on single-atom catalysts (SACs). Moreover, V-N-Ru/NC and V-N-Os/NC are systematically screened out as promising e-NRR catalysts, with extremely low limiting potentials of −0.20 and −0.18 V, respectively. Furthermore, the adsorption site competition between *N₂ and *H, as well as the competitive twin reactions of hydrogen evolution reaction (HER) on intermediates (N_nH_m) during the e-NRR process, is systematically evaluated to form a remodeling insight for the reactions in mechanism, and the e-NRR of new proposed dual-atom catalysts (DACs) is strategically optimized for its high-efficiency performance potential via our remolding insight in e-NRR mechanism. This work provides new ideas and insights for the design and mechanism of e-NRR catalysts and an effective strategy for rapidly screening highly efficient e-NRR catalysts.