ΔE 13.8, fair: the same colour family, but not a straight swap. Buff is a little darker, cooler than Hearthborn.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 14). Buff is a little darker, cooler than Hearthborn.
The same difference applies the other way round: Hearthborn is a little lighter, 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 Hearthborn on the colour wheel See Buff on the colour wheel
All matches: Hearthborn equivalents · Buff equivalents