ΔE 7.5, close: similar, with a visible difference side by side. Green Brown is a little darker, warmer than Hay Color.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Green Brown is a little darker, warmer than Hay Color.
The same difference applies the other way round: Hay Color is a little lighter, cooler.
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 Hay Color on the colour wheel See Green Brown on the colour wheel
All matches: Hay Color equivalents · Green Brown equivalents