IJA #29 Ki Midori iro (Yel- low-Green) vs Greatcoat Green

How close are they?

ΔE 7.7, close: similar, with a visible difference side by side. Greatcoat Green is more muted than IJA #29 Ki Midori iro (Yel- low-Green).

Can I use Greatcoat Green instead of IJA #29 Ki Midori iro (Yel- low-Green)?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Greatcoat Green is more muted than IJA #29 Ki Midori iro (Yel- low-Green).

Can I use IJA #29 Ki Midori iro (Yel- low-Green) instead of Greatcoat Green?

The same difference applies the other way round: IJA #29 Ki Midori iro (Yel- low-Green) is 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.