Magnetic topological insulators, characterized by their unique topological states, exhibit novel transport properties that have attracted great interest in recent years. Here, we report the magnetotransport of a magnetic topological-insulator heterostructure composed of $\mathrm{C}{\mathrm{r}}_2\mathrm{G}{\mathrm{e}}_2\mathrm{T}{\mathrm{e}}_6$ (CGT), ${\left(\mathrm{B}{\mathrm{i}}_{1-x}\mathrm{S}{\mathrm{b}}_x\right)}_2\mathrm{T}{\mathrm{e}}_3$ (BST), and $\mathrm{E}{\mathrm{u}}_3\mathrm{F}{\mathrm{e}}_5{\mathrm{O}}_{12}$ (EuIG). Inequivalent exchange fields were introduced on the top and bottom surfaces of BST via magnetic proximity effect, giving rise to superimposed anomalous Hall effect (AHE) signals with opposite polarities. The negative AHE, which persists up to room temperature, originates from the EuIG/BST interface, while the positive AHE, generated at the CGT/BST interface, disappears above $85\pm 5\mathrm{K}$. This behavior reflects a ferrimagneticlike state with opposite Berry curvatures at the top and bottom BST surfaces, indicative of the layer Hall effect in the absence of external electric fields. As the temperature decreased, the overall AHE signal was gradually dominated by the CGT/BST interface and reached a largest magnitude of 666 Ω ($\sim 0.1{\mathrm{e}}^2/\mathrm{h}$) at 2 K. Systematic thickness-dependent studies revealed a critical BST thickness ($\sim 4$ nm), below which the top and bottom surface states hybridize, suppressing the AHE. This study explores interfacial magnetism and Berry curvature engineering with different magnetic insulators in heterostructures, offering a rich playground to study the interplay among charge, spin, and band topology in magnetic topological systems.

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• Magnetotransport
• Magnetic thin films
• Topological insulators
• Molecular beam epitaxy
• Sputtering
• Transport techniques