Fairy Pink vs Cobalt Violet Hue

How close are they?

ΔE 17.6, loose: different enough that you should pick on purpose. Cobalt Violet Hue is noticeably darker, more saturated, warmer than Fairy Pink.

Can I use Cobalt Violet Hue instead of Fairy Pink?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Cobalt Violet Hue is noticeably darker, more saturated, warmer than Fairy Pink.

Can I use Fairy Pink instead of Cobalt Violet Hue?

The same difference applies the other way round: Fairy Pink is noticeably lighter, more muted, 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.