ΔE 5.9, very close: most people won’t see a difference side by side. Briar Queen Chill is more saturated, cooler than Sword Grey. They are different kinds of paint: AMMO by Mig Sword Grey is an opaque base/layer paint and Citadel Briar Queen Chill is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Yes, for most jobs. Very close match (ΔE 6). Briar Queen Chill is more saturated, cooler than Sword Grey. They are different kinds of paint.
The same difference applies the other way round: Sword Grey 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 Sword Grey on the colour wheel See Briar Queen Chill on the colour wheel
All matches: Sword Grey equivalents · Briar Queen Chill equivalents