Terminal velocities as a function of effective temperature: The results from this work (red diamonds) are compared to the values from Hawcroft et al. (2024, blue circles). The thick solid red and solid blue lines show the resulting relation when considering only supergiants (BSGs and OBSGs). The thick red dotted line shows the relation for only BSGs, but excludes the peculiar AzV 104. The blue dot-dashed line shows the linear relation derived for all SMC OB stars (of all types and classes) in the Hawcroft et al. (2024) paper also considering the literature results. Conversely, the dark blue dashed line refers to the LMC.