ΔE 12.6, fair: the same colour family, but not a straight swap. Yellow Ochre is a little darker, more muted than Plague Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Yellow Ochre is a little darker, more muted than Plague Brown.
The same difference applies the other way round: Plague Brown 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 Plague Brown on the colour wheel See Yellow Ochre on the colour wheel
All matches: Plague Brown equivalents · Yellow Ochre equivalents