ΔE 12.8, fair: the same colour family, but not a straight swap. IJN Ash Grey is a little darker, more muted, cooler than Light Battle Dress.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). IJN Ash Grey is a little darker, more muted, cooler than Light Battle Dress.
The same difference applies the other way round: Light Battle Dress is a little lighter, more saturated, warmer.
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 Light Battle Dress on the colour wheel See IJN Ash Grey on the colour wheel
All matches: Light Battle Dress equivalents · IJN Ash Grey equivalents