ΔE 22.2, loose: different enough that you should pick on purpose. Khardic Flesh is noticeably darker, much more saturated than Kislev Flesh.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Khardic Flesh is noticeably darker, much more saturated than Kislev Flesh.
The same difference applies the other way round: Kislev Flesh is noticeably lighter, much 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 Kislev Flesh on the colour wheel See Khardic Flesh on the colour wheel
All matches: Kislev Flesh equivalents · Khardic Flesh equivalents