ΔE 10.7, fair: the same colour family, but not a straight swap. Blue Horror is a little lighter, more saturated, cooler than Sword Grey.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Blue Horror is a little lighter, more saturated, cooler than Sword Grey.
The same difference applies the other way round: Sword Grey is a little darker, 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 Sword Grey on the colour wheel See Blue Horror on the colour wheel
All matches: Sword Grey equivalents · Blue Horror equivalents