ΔE 12.7, fair: the same colour family, but not a straight swap. Thornwood Green is a little lighter, more saturated, warmer than Mid Feldgrau.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Thornwood Green is a little lighter, more saturated, warmer than Mid Feldgrau.
The same difference applies the other way round: Mid Feldgrau is a little darker, more muted, 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 Mid Feldgrau on the colour wheel See Thornwood Green on the colour wheel
All matches: Mid Feldgrau equivalents · Thornwood Green equivalents