ΔE 9.4, close: similar, with a visible difference side by side. Medium Sea Grey is a little darker, more muted than Grey Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 9). Medium Sea Grey is a little darker, more muted than Grey Green.
The same difference applies the other way round: Grey Green is a little lighter, 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.
See Grey Green on the colour wheel See Medium Sea Grey on the colour wheel
All matches: Grey Green equivalents · Medium Sea Grey equivalents