Anodized Violet vs Leadbelcher

How close are they?

ΔE 15.6, loose: different enough that you should pick on purpose. Leadbelcher is noticeably darker, more muted than Anodized Violet.

Can I use Leadbelcher instead of Anodized Violet?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Leadbelcher is noticeably darker, more muted than Anodized Violet.

Can I use Anodized Violet instead of Leadbelcher?

The same difference applies the other way round: Anodized Violet is noticeably lighter, 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.