Hardness ratio diagrams indicating the applied selection (dashed black line), the distribution of simulated absorbed blackbody spectra (solid lines), and the position of the synthetic thermally emitting INS population of Pires et al. (2017; black circles). The known population of XDINSs (dubbed the ‘magnificent seven’), on the German part of the eROSITA sky, in red, and the three middle-aged thermally emitting rotation-powered pulsars, PSR B0656+14, Geminga, and PSR B1055−52 (dubbed the ‘three musketeers’) in green are indicated along with the location of the two INS candidates discussed in this work (magenta). The hardness ratios were computed between the 0.2–0.5 keV and 0.5–1.0 keV (HR1), 0.5–1.0 keV and 1.0–2.0 keV (HR2), and 1.0–2.0 keV and 2.0–5.0 keV (HR3) bands.