ΔE 12.3, fair: the same colour family, but not a straight swap. Brethil Blush is a little lighter, more muted than Medium Flesh Tone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Brethil Blush is a little lighter, more muted than Medium Flesh Tone.
The same difference applies the other way round: Medium Flesh Tone is a little darker, more saturated.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See Medium Flesh Tone on the colour wheel See Brethil Blush on the colour wheel
All matches: Medium Flesh Tone equivalents · Brethil Blush equivalents