ΔE 11.2, fair: the same colour family, but not a straight swap. Screaming Skull is a little lighter, more muted than Buff.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Screaming Skull is a little lighter, more muted than Buff.
The same difference applies the other way round: Buff 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 Buff on the colour wheel See Screaming Skull on the colour wheel
All matches: Buff equivalents · Screaming Skull equivalents