Sky Green vs Wraithbone

How close are they?

ΔE 16.1, loose: different enough that you should pick on purpose. Wraithbone is a little lighter, more muted, warmer than Sky Green.

Can I use Wraithbone instead of Sky Green?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Wraithbone is a little lighter, more muted, warmer than Sky Green.

Can I use Sky Green instead of Wraithbone?

The same difference applies the other way round: Sky Green is a little darker, more saturated, 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.