Barbarian Flesh vs Bone Khaki

How close are they?

ΔE 28.1, loose: different enough that you should pick on purpose. Bone Khaki is a little darker, much more muted than Barbarian Flesh.

Can I use Bone Khaki instead of Barbarian Flesh?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 28). Bone Khaki is a little darker, much more muted than Barbarian Flesh.

Can I use Barbarian Flesh instead of Bone Khaki?

The same difference applies the other way round: Barbarian Flesh is a little lighter, much 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.