Hertzprung–Russell diagram (HRD) of the BLOeM survey highlighting the BAF supergiant sample studied in this article with large star symbols colour-coded based on spectral type, as indicated by the legend. The three targets with the black circles indicate the only targets in this sample that have a clear indication of binarity: BLOeM 4-072, BLOeM 6-006, and BLOeM 6-008. The three targets with the black squares indicate targets that display a binary motion characteristic of long orbital periods: BLOeM 1-114, BLOeM 3-106, and BLOeM 8-001. Stellar parameters are determined using a calibration to spectral types by Paper I. Grey points show the entire BLOeM sample and stellar tracks from the extended grid of Schootemeijer et al. (2019) with mass-dependent overshooting (described in Appendix B of Hastings et al. 2021). The black marker with error bars on the left gives an indication of the typical uncertainties on the stellar parameters. The solid red line shows the magnitude limit imposed by the BLOeM survey target selection. The dashed red line is the Humphreys–Davidson (HD) limit, the cool part of which is shown as the revised-down limit in the SMC from Davies et al. (2018).