Kislev Flesh vs Rosy Highlight

How close are they?

ΔE 8.7, close: similar, with a visible difference side by side. Rosy Highlight is a little lighter, more muted than Kislev Flesh.

Can I use Rosy Highlight instead of Kislev Flesh?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Rosy Highlight is a little lighter, more muted than Kislev Flesh.

Can I use Kislev Flesh instead of Rosy Highlight?

The same difference applies the other way round: Kislev Flesh 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.