ΔE 11.7, fair: the same colour family, but not a straight swap. Undergrowth Green is more saturated than Resedagrün (RAL 6011).
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Undergrowth Green is more saturated than Resedagrün (RAL 6011).
The same difference applies the other way round: Resedagrün (RAL 6011) is 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 Resedagrün (RAL 6011) on the colour wheel See Undergrowth Green on the colour wheel
All matches: Resedagrün (RAL 6011) equivalents · Undergrowth Green equivalents