ΔE 18.7, loose: different enough that you should pick on purpose. Dark Flesh Tone is noticeably darker, more saturated than Red Flesh.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Dark Flesh Tone is noticeably darker, more saturated than Red Flesh.
The same difference applies the other way round: Red Flesh is noticeably lighter, more muted.
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 Red Flesh on the colour wheel See Dark Flesh Tone on the colour wheel
All matches: Red Flesh equivalents · Dark Flesh Tone equivalents