ΔE 11.6, fair: the same colour family, but not a straight swap. Ratskin Flesh is noticeably lighter than Orange Brown.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Ratskin Flesh is noticeably lighter than Orange Brown.
The same difference applies the other way round: Orange Brown is noticeably darker.
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 Orange Brown on the colour wheel See Ratskin Flesh on the colour wheel
All matches: Orange Brown equivalents · Ratskin Flesh equivalents