ΔE 16.1, loose: different enough that you should pick on purpose. Rotten Flesh is noticeably lighter, more saturated, cooler than Elfwood Brown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Rotten Flesh is noticeably lighter, more saturated, cooler than Elfwood Brown.
The same difference applies the other way round: Elfwood Brown is noticeably darker, 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 Elfwood Brown on the colour wheel See Rotten Flesh on the colour wheel
All matches: Elfwood Brown equivalents · Rotten Flesh equivalents