ΔE 18.6, loose: different enough that you should pick on purpose. Succubus Skin is noticeably lighter, more muted, cooler than Knight-Questor Flesh.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Succubus Skin is noticeably lighter, more muted, cooler than Knight-Questor Flesh.
The same difference applies the other way round: Knight-Questor Flesh is noticeably darker, more saturated, 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 Knight-Questor Flesh on the colour wheel See Succubus Skin on the colour wheel
All matches: Knight-Questor Flesh equivalents · Succubus Skin equivalents