T_e-based metallicities and strong-line ratios for the z > 9 sample. Direct oxygen abundances are represented by hot pink square markers, with 3σ upper limits in pale pink. We compare to various literature strong-line diagnostics: the solid and dashed blue relations show Laseter et al. (2024) and Scholte et al. (2025) $\widehat{R}$ calibrations, while the solid and dashed black curves are Ne3O2, R3, R2, R23, O32 diagnostics from Sanders et al. (2024), Sanders et al. (2025) and Nakajima et al. (2022), respectively.