ΔE 16.2, loose: different enough that you should pick on purpose. Elf Skin Tone is a little lighter, more muted than Blood Tracker Brown.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Elf Skin Tone is a little lighter, more muted than Blood Tracker Brown.
The same difference applies the other way round: Blood Tracker Brown is a little darker, more saturated.
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 Blood Tracker Brown on the colour wheel See Elf Skin Tone on the colour wheel
All matches: Blood Tracker Brown equivalents · Elf Skin Tone equivalents