Moldy Wine vs Shadow Red

How close are they?

ΔE 15.3, loose: different enough that you should pick on purpose. Shadow Red is noticeably darker, more muted than Moldy Wine.

Can I use Shadow Red instead of Moldy Wine?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 15). Shadow Red is noticeably darker, more muted than Moldy Wine.

Can I use Moldy Wine instead of Shadow Red?

The same difference applies the other way round: Moldy Wine 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.