ΔE 6.4, close: similar, with a visible difference side by side. Transparent Brown is more saturated, warmer than Strong Skin Wash. They are different kinds of paint: Army Painter Strong Skin Wash is a wash/shade and Green Stuff World Transparent Brown is an ink, glaze or transparent 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 6). Transparent Brown is more saturated, warmer than Strong Skin Wash. They are different kinds of paint.
The same difference applies the other way round: Strong Skin Wash is more muted, cooler.
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 Strong Skin Wash on the colour wheel See Transparent Brown on the colour wheel
All matches: Strong Skin Wash equivalents · Transparent Brown equivalents