ΔE 11.4, fair: the same colour family, but not a straight swap. Castellan Green is more saturated, cooler than IJA Kawasaki Green.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Castellan Green is more saturated, cooler than IJA Kawasaki Green.
The same difference applies the other way round: IJA Kawasaki Green is more muted, 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 IJA Kawasaki Green on the colour wheel See Castellan Green on the colour wheel
All matches: IJA Kawasaki Green equivalents · Castellan Green equivalents