ΔE 9.1, close: similar, with a visible difference side by side. Warrior Skin is more saturated than Earth. They are different kinds of paint: AMMO by Mig Earth is an opaque base/layer paint and Army Painter Warrior Skin is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Warrior Skin is more saturated than Earth. They are different kinds of paint.
The same difference applies the other way round: Earth is 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 Earth on the colour wheel See Warrior Skin on the colour wheel
All matches: Earth equivalents · Warrior Skin equivalents