Advanced Flesh Tone vs Rosy Flesh

How close are they?

ΔE 6.6, close: similar, with a visible difference side by side. Rosy Flesh is a little lighter, more saturated than Advanced Flesh Tone.

Can I use Rosy Flesh instead of Advanced Flesh Tone?

Usually, if you are not matching paint already on the model. Close match (ΔE 7). Rosy Flesh is a little lighter, more saturated than Advanced Flesh Tone.

Can I use Advanced Flesh Tone instead of Rosy Flesh?

The same difference applies the other way round: Advanced Flesh Tone is a little darker, 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.