ΔE 14.7, fair: the same colour family, but not a straight swap. Space Wolves Grey is noticeably darker, more saturated than Ashen Stone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 15). Space Wolves Grey is noticeably darker, more saturated than Ashen Stone.
The same difference applies the other way round: Ashen Stone is noticeably lighter, more muted.
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 Ashen Stone on the colour wheel See Space Wolves Grey on the colour wheel
All matches: Ashen Stone equivalents · Space Wolves Grey equivalents