ΔE 11.2, fair: the same colour family, but not a straight swap. Underhive Ash is cooler than Light Sand FS-33727.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Underhive Ash is cooler than Light Sand FS-33727.
The same difference applies the other way round: Light Sand FS-33727 is 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 Light Sand FS-33727 on the colour wheel See Underhive Ash on the colour wheel
All matches: Light Sand FS-33727 equivalents · Underhive Ash equivalents