Rest-frame SED peak photon energy E_peak versus the isotropic-equivalent energy, E_iso, for our NSNS (left panel) and BHNS (right panel) populations. The filled green coloured regions contain 50%, 90%, and 99% of the binaries both GRB prompt- and ET-detectable. The magenta lines contain 50%, 90%, and 99% (solid, dashed, and dotted, respectively) of the GRB prompt-detectable binaries. The black dashed line contains 90% of the ET-detectable binaries. The black dots with error bars represent an SGRB sample for comparison (Salafia et al. 2023). The orange dot is GRB170817A. We assumed for both populations the same jet half-opening angle θ_j = 3.4 deg. In the BHNS panel, we also show with orange solid lines the 50% contour for radio peaks when assuming θ_j = 15 deg.