Viridian Green Hue vs Ink Green

How close are they?

ΔE 19.1, loose: different enough that you should pick on purpose. Ink Green is much more saturated, warmer than Viridian Green Hue.

Can I use Ink Green instead of Viridian Green Hue?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Ink Green is much more saturated, warmer than Viridian Green Hue.

Can I use Viridian Green Hue instead of Ink Green?

The same difference applies the other way round: Viridian Green Hue is much more muted, cooler.

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.