Storm Wolf vs Etherium Blue

How close are they?

ΔE 6.2, close: similar, with a visible difference side by side. Etherium Blue is more saturated, cooler than Storm Wolf.

Can I use Etherium Blue instead of Storm Wolf?

Usually, if you are not matching paint already on the model. Close match (ΔE 6). Etherium Blue is more saturated, cooler than Storm Wolf.

Can I use Storm Wolf instead of Etherium Blue?

The same difference applies the other way round: Storm Wolf is more muted, 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.