Stacked [O III]λ5007 spectra of type-2 (red) and type-1 (blue) AGN from SUPER with L_bol ∼ 10^{44.8 − 46.5} (orange shading in Fig. 8), resulting from integrated (aperture with a radius of 0.25″), subtracted [O III] spectra with S/N > 5. The integrated spectra were averaged by the inverse of the squared noise, and then the resulting stacked spectrum was normalised to the final [O III] peak. Comparing the two stacked spectra, we find a statistically significant (2.7σ) difference in the [O III] blue wing, which is more prominent in the type-2 spectrum of about 500 km s⁻¹ compared to the type-1 stack.