Pallid Wych Flesh vs Khaki Highlight

How close are they?

ΔE 7.6, close: similar, with a visible difference side by side. Khaki Highlight is more saturated than Pallid Wych Flesh.

Can I use Khaki Highlight instead of Pallid Wych Flesh?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Khaki Highlight is more saturated than Pallid Wych Flesh.

Can I use Pallid Wych Flesh instead of Khaki Highlight?

The same difference applies the other way round: Pallid Wych Flesh 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.