Improved oxygen electrocatalysis is crucial for the ever-growing energy demand. Metal-nitrogen-carbon (M-N-C) materials are promising candidates for catalysts. Their activity is tunable via varying electronic and geometric properties, such as porosity. Because of the difficulty in modeling porosity, M-N-Cs with variable surface curvature remained largely unexplored. In this work, we developed a realistic in-pore dual-atom site M-N-C model and applied density functional theory to investigate the surface curvature effect on oxygen reduction and evolution reactions. We show that surface curving tailors both scaling relations and energy barriers. Thus, we predict that adjusting the surface curvature can improve the catalytic activity toward mono- and bifunctional oxygen electrocatalysis.