ΔE 6.9, close: similar, with a visible difference side by side. Phthalo Green (Blue Shade) is more saturated than Waystone Green. They are different kinds of paint: Citadel Waystone Green is a technical paint or medium and Golden Phthalo Green (Blue Shade) is an opaque base/layer paint, so they won’t behave the same on the model even where the colour is close.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Phthalo Green (Blue Shade) is more saturated than Waystone Green. They are different kinds of paint.
The same difference applies the other way round: Waystone Green is more muted.
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.
See Waystone Green on the colour wheel See Phthalo Green (Blue Shade) on the colour wheel
All matches: Waystone Green equivalents · Phthalo Green (Blue Shade) equivalents