ΔE 9.6, close: similar, with a visible difference side by side. Death Guard Green is a little darker, more muted than Resedagrün (RAL 6011).
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Death Guard Green is a little darker, more muted than Resedagrün (RAL 6011).
The same difference applies the other way round: Resedagrün (RAL 6011) 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 Resedagrün (RAL 6011) on the colour wheel See Death Guard Green on the colour wheel
All matches: Resedagrün (RAL 6011) equivalents · Death Guard Green equivalents