ΔE 7.1, close: similar, with a visible difference side by side. Intermediate Blue is a little lighter than IJN Gray (Sasebo Arsenal).
Usually, if you are not matching paint already on the model. Close match (ΔE 7). Intermediate Blue is a little lighter than IJN Gray (Sasebo Arsenal).
The same difference applies the other way round: IJN Gray (Sasebo Arsenal) is a little darker.
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 IJN Gray (Sasebo Arsenal) on the colour wheel See Intermediate Blue on the colour wheel
All matches: IJN Gray (Sasebo Arsenal) equivalents · Intermediate Blue equivalents