Khorne Red vs Wonka Violet

How close are they?

ΔE 19.0, loose: different enough that you should pick on purpose. Wonka Violet is a little lighter, cooler than Khorne Red.

Can I use Wonka Violet instead of Khorne Red?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Wonka Violet is a little lighter, cooler than Khorne Red.

Can I use Khorne Red instead of Wonka Violet?

The same difference applies the other way round: Khorne Red is a little darker, 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.