ΔE 11.0, fair: the same colour family, but not a straight swap. Idrian Flesh is more saturated, cooler than Agrellan Badland. They are different kinds of paint: Citadel Agrellan Badland is a technical paint or medium and Formula P3 Idrian Flesh is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Idrian Flesh is more saturated, cooler than Agrellan Badland. They are different kinds of paint.
The same difference applies the other way round: Agrellan Badland is more muted, 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 Agrellan Badland on the colour wheel See Idrian Flesh on the colour wheel
All matches: Agrellan Badland equivalents · Idrian Flesh equivalents