ΔE 12.6, fair: the same colour family, but not a straight swap. Longbeard Grey is a little lighter, more muted than Nakajima Interior Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Longbeard Grey is a little lighter, more muted than Nakajima Interior Green.
The same difference applies the other way round: Nakajima Interior Green is a little darker, 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 Nakajima Interior Green on the colour wheel See Longbeard Grey on the colour wheel
All matches: Nakajima Interior Green equivalents · Longbeard Grey equivalents