Kraken Lavender vs White Star

How close are they?

ΔE 19.2, loose: different enough that you should pick on purpose. White Star is noticeably lighter, more muted than Kraken Lavender.

Can I use White Star instead of Kraken Lavender?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). White Star is noticeably lighter, more muted than Kraken Lavender.

Can I use Kraken Lavender instead of White Star?

The same difference applies the other way round: Kraken Lavender is noticeably 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.