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Despite decades of recognition regarding the significant influence of wettability on multiphase flow, the wettability dependency of multiphase displacement in different geometric-confined porous media remains controversial in pore-scale studies. Here, we report transitions from monotonic to nonmonotonic wettability dependency during multiphase displacement across 2D and 3D porous media using a combination of an improved dynamic pore-network model and microfluidic experiments. To link pore-scale events to macroscopic displacement patterns, we analyze microscopic flow dynamics through direct numerical simulations. In 2D porous media, we observe a monotonic wettability rule where capillary fingering transitions to compact displacement as the flow shifts from drainage to imbibition, consistent across various capillary number conditions. However, 2.5D and 3D porous media present a more complex phase diagram, controlled by capillary number and contact angle. The 3D pore geometry will trigger new pore-scale phenomena, such as the coupling of capillary fingering with snap-off events during strong drainage, and frequent snap-off events during strong imbibition. These pore-scale events are closely related to capillary numbers, which lead to varied wettability dependencies. Our findings provide new insights into wettability-dependent multiphase displacement in various natural porous media and offer design principles for engineering artificial porous media to achieve desired immiscible displacement behaviors.