Desert Olive Green vs Kobold Grey

How close are they?

ΔE 6.1, close: similar, with a visible difference side by side. Kobold Grey is a little darker than Desert Olive Green.

Can I use Kobold Grey instead of Desert Olive Green?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Kobold Grey is a little darker than Desert Olive Green.

Can I use Desert Olive Green instead of Kobold Grey?

The same difference applies the other way round: Desert Olive Green is a little lighter.

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.