With the intriguing coexistence of local magnetic orders and nonlocal valence bond patterns, unconventional magnetic plateau phases in geometrically frustrated quantum systems have attracted significant attention. This work investigates the spin-1/2 anisotropic kagome antiferromagnet, uncovering an exotic transition between two distinct valence bond patterns within the 1/9 magnetization plateau, where the fidelity between them is nearly equal to zero. By tuning the exchange anisotropy, we observe a spatial inversion of the valence bond pattern, accompanied by singularities at the transition boundary that is indicated by peaks in local magnetizations, nearest-neighbor correlations, entanglement entropy, and correlation length. Particularly in an external field $0.33<h<0.4$ along the spin-$z$ direction, tuning the exchange anisotropy induces a reentrant phenomenon, where the system enters from the type-$\mathcal{A}$ 1/9 plateau to a nonplateau region and back to the type-$\mathcal{B}$ 1/9 plateau with an inverted valence bond pattern. As the external field decreases to $0.29<h<0.33$, the nonplateau region narrows, reducing to a direct phase transition between these two types of 1/9 plateaus. Our findings highlight the intricate interplay of quantum fluctuations arising from nonlocal geometrical frustration and local exchange anisotropy, shedding light on exotic quantum phenomena in frustrated spin systems.

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• Phase diagrams
• Quantum criticality
• Valence bond solid
• Antiferromagnets
• Kagome lattice
• Tensor network methods
• XYZ model