Flayed One Flesh vs Pale Flesh

How close are they?

ΔE 8.8, close: similar, with a visible difference side by side. Pale Flesh is a little darker, more muted than Flayed One Flesh.

Can I use Pale Flesh instead of Flayed One Flesh?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Pale Flesh is a little darker, more muted than Flayed One Flesh.

Can I use Flayed One Flesh instead of Pale Flesh?

The same difference applies the other way round: Flayed One Flesh is a little lighter, more saturated.

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.