ΔE 8.6, close: similar, with a visible difference side by side. Plague Brown is a little lighter, more saturated than Zamesi Desert.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Plague Brown is a little lighter, more saturated than Zamesi Desert.
The same difference applies the other way round: Zamesi Desert is a little darker, 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.
See Zamesi Desert on the colour wheel See Plague Brown on the colour wheel
All matches: Zamesi Desert equivalents · Plague Brown equivalents