Idrian Flesh vs Beige Red

How close are they?

ΔE 9.2, close: similar, with a visible difference side by side. Beige Red is a little lighter, more muted than Idrian Flesh.

Can I use Beige Red instead of Idrian Flesh?

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

Can I use Idrian Flesh instead of Beige Red?

The same difference applies the other way round: Idrian 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.