Sliding-controllable on-off states in <inline-formula><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" id="TIMEQ1"><mml:msub><mml:mrow><mml:mi>M</mml:mi><mml:mi>A</mml:mi><mml:mi>X</mml:mi></mml:mrow><mml:mn>3</mml:mn></mml:msub></mml:math></inline-formula>-based (\textit{M}= Mn, Ni; \textit{A}= Si, Ge; \textit{X}= S, Se) van der Waals tunnel junctionsnowstartneedtodelete Sliding-controllable on-off states in ${MAX}_3$-based (<italic>M</italic>= Mn, Ni; <italic>A</italic>= Si, Ge; <italic>X</italic>= S, Se) van der Waals tunnel junctionsnowendneedtodelete

Two-dimensional (2D) materials hold remarkable promise for high-density memory applications, yet precise modulation of interface properties in van der Waals (vdW) tunnel junctions remains a critical challenge. In this work, we systematically investigate the interface contact and charge transport properties of MAX$_3$-based vdW tunnel junctions (M= Mn, Ni; A= Si, Ge; X= S, Se). Our findings demonstrate that controlled sliding between atomic layers enables deterministic regulation of both the Schottky barrier height and magnetic moment orientation, driven by layer-dependent charge redistribution at selenium-terminated interfaces. First-principles calculations combined with non-equilibrium Green's function simulations reveal substantial improvements in tunneling resistance ($\sim$$6\times10^5$%) and tunneling magnetoresistance ($\sim$$10^{10}$%) achieved through interface engineering. These results provide a general strategy for tailoring quantum transport in 2D vdW heterostructures, offering a versatile platform for reconfigurable memory devices with atomic-scale precision.