ΔE 12.9, fair: the same colour family, but not a straight swap. T'au Light Ochre is a little darker, more saturated than Brethil Blush.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). T'au Light Ochre is a little darker, more saturated than Brethil Blush.
The same difference applies the other way round: Brethil Blush is a little lighter, more muted.
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 Brethil Blush on the colour wheel See T'au Light Ochre on the colour wheel
All matches: Brethil Blush equivalents · T'au Light Ochre equivalents