ΔE 11.5, fair: the same colour family, but not a straight swap. IJN Gray Mitsubishi is a little darker, more muted than Blue Horror.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). IJN Gray Mitsubishi is a little darker, more muted than Blue Horror.
The same difference applies the other way round: Blue Horror is a little lighter, 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 Blue Horror on the colour wheel See IJN Gray Mitsubishi on the colour wheel
All matches: Blue Horror equivalents · IJN Gray Mitsubishi equivalents