ΔE 6.9, close: similar, with a visible difference side by side. Dark Sea Blue is a little darker than RLM 70 Black Green.
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Dark Sea Blue is a little darker than RLM 70 Black Green.
The same difference applies the other way round: RLM 70 Black Green is a little lighter.
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 RLM 70 Black Green on the colour wheel See Dark Sea Blue on the colour wheel
All matches: RLM 70 Black Green equivalents · Dark Sea Blue equivalents