ΔE 11.5, fair: the same colour family, but not a straight swap. Gnome Flesh is a little lighter, more saturated, warmer than Kislev Flesh.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Gnome Flesh is a little lighter, more saturated, warmer than Kislev Flesh.
The same difference applies the other way round: Kislev Flesh is a little darker, more muted, cooler.
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 Gnome Flesh on the colour wheel
All matches: Kislev Flesh equivalents · Gnome Flesh equivalents