Verdigris vs Forest of Shadows

How close are they?

ΔE 21.6, loose: different enough that you should pick on purpose. Forest of Shadows is noticeably darker, more muted than Verdigris.

Can I use Forest of Shadows instead of Verdigris?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 22). Forest of Shadows is noticeably darker, more muted than Verdigris.

Can I use Verdigris instead of Forest of Shadows?

The same difference applies the other way round: Verdigris 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.