ΔE 12.4, fair: the same colour family, but not a straight swap. Plague Brown is a little darker, more muted than Sun Stone.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Plague Brown is a little darker, more muted than Sun Stone.
The same difference applies the other way round: Sun Stone is a little lighter, 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 Sun Stone on the colour wheel See Plague Brown on the colour wheel
All matches: Sun Stone equivalents · Plague Brown equivalents