ΔE 10.9, fair: the same colour family, but not a straight swap. Neutral Grey is a little lighter, more muted than Terror Blue-Grey.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Neutral Grey is a little lighter, more muted than Terror Blue-Grey.
The same difference applies the other way round: Terror Blue-Grey 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 Terror Blue-Grey on the colour wheel See Neutral Grey on the colour wheel
All matches: Terror Blue-Grey equivalents · Neutral Grey equivalents