Two-dimensional Janus antiferromagnetic (AFM) materials provide a unique broken-symmetry environment to explore the interplay between spin, valley, and layer degrees of freedom. In this work, we investigate the Janus MXene bilayer ${\mathrm{Cr}}_2\mathrm{CHF}$, which maintains a robust AFM ground state with a high Néel temperature ($T_{\mathrm{N}}=475\mathrm{K}$), ensuring magnetic stability well above room temperature. To elucidate the underlying physics, we develop a low-energy $\mathbf{k}·\mathbf{p}$ model, demonstrating that the intrinsic vertical dipole of the Janus layers, in synergy with interlayer exchange coupling, plays a pivotal role in lifting the valley degeneracy. Our analysis reveals that the Janus-induced internal electric field acts as a persistent bias, facilitating substantial valley splitting and contrasting Berry curvature. Furthermore, we show that interlayer sliding and external electric fields are functionally equivalent knobs for tuning the valley properties. A sliding-mediated ferroelectriclike switching is identified to reverse the layer-resolved valley polarization, enabling nonvolatile electrical control of the anomalous valley Hall effect. These findings establish bilayer ${\mathrm{Cr}}_2\mathrm{CHF}$ as a promising platform for integrated, high-temperature valleytronic memory and logic devices.

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• Ferroelectricity
• Valleytronics
• Topological materials
• First-principles calculations