Strong Skin Wash vs Agrax Earthshade

How close are they?

ΔE 16.7, loose: different enough that you should pick on purpose. Agrax Earthshade is a little lighter, more muted, warmer than Strong Skin Wash.

Can I use Agrax Earthshade instead of Strong Skin Wash?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 17). Agrax Earthshade is a little lighter, more muted, warmer than Strong Skin Wash.

Can I use Strong Skin Wash instead of Agrax Earthshade?

The same difference applies the other way round: Strong Skin Wash is a little darker, more saturated, 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.