Green vs Green Yellow

How close are they?

ΔE 9.5, close: similar, with a visible difference side by side. Green Yellow is a little darker, more muted than Green.

Can I use Green Yellow instead of Green?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Green Yellow is a little darker, more muted than Green.

Can I use Green instead of Green Yellow?

The same difference applies the other way round: Green is a little 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.