ΔE 11.7, fair: the same colour family, but not a straight swap. Gnoll Brown is a little darker, cooler than Catachan Flesh.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Gnoll Brown is a little darker, cooler than Catachan Flesh.
The same difference applies the other way round: Catachan Flesh is a little lighter, warmer.
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 Catachan Flesh on the colour wheel See Gnoll Brown on the colour wheel
All matches: Catachan Flesh equivalents · Gnoll Brown equivalents