Andalusian Earth vs Flesh Wash

How close are they?

ΔE 21.8, loose: different enough that you should pick on purpose. Flesh Wash is noticeably lighter, more saturated, cooler than Andalusian Earth.

Can I use Flesh Wash instead of Andalusian Earth?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Flesh Wash is noticeably lighter, more saturated, cooler than Andalusian Earth.

Can I use Andalusian Earth instead of Flesh Wash?

The same difference applies the other way round: Andalusian Earth is noticeably darker, 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.