ΔE 11.7, fair: the same colour family, but not a straight swap. Chromium Oxide Green Dark is a little lighter, cooler than Military Shader. They are different kinds of paint: Army Painter Military Shader is a wash/shade and Golden Chromium Oxide Green Dark is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Chromium Oxide Green Dark is a little lighter, cooler than Military Shader. They are different kinds of paint.
The same difference applies the other way round: Military Shader is a little darker, warmer.
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 Military Shader on the colour wheel See Chromium Oxide Green Dark on the colour wheel
All matches: Military Shader equivalents · Chromium Oxide Green Dark equivalents