ΔE 18.5, loose: different enough that you should pick on purpose. Transparent Brown Iron Oxide is a little darker, more saturated, warmer than Ratskin Flesh.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Transparent Brown Iron Oxide is a little darker, more saturated, warmer than Ratskin Flesh.
The same difference applies the other way round: Ratskin Flesh is a little lighter, more muted, cooler.
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 Transparent Brown Iron Oxide on the colour wheel
All matches: Ratskin Flesh equivalents · Transparent Brown Iron Oxide equivalents