ΔE 10.0, fair: the same colour family, but not a straight swap. Rust Orange is a little darker, more saturated, cooler than Ratskin Flesh.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Rust Orange is a little darker, more saturated, cooler than Ratskin Flesh.
The same difference applies the other way round: Ratskin Flesh is a little lighter, more muted, 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 Ratskin Flesh on the colour wheel See Rust Orange on the colour wheel
All matches: Ratskin Flesh equivalents · Rust Orange equivalents