ΔE 12.6, fair: the same colour family, but not a straight swap. Transparent Ochre is more saturated than Golfag Brown. They are different kinds of paint: Citadel Golfag Brown is an opaque base/layer paint and Green Stuff World Transparent Ochre is an ink, glaze or transparent paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Transparent Ochre is more saturated than Golfag Brown. They are different kinds of paint.
The same difference applies the other way round: Golfag Brown is 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 Golfag Brown on the colour wheel See Transparent Ochre on the colour wheel
All matches: Golfag Brown equivalents · Transparent Ochre equivalents