ΔE 10.0, close: similar, with a visible difference side by side. Oxford Blue is a little lighter, more muted than Triumphant Navy.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Oxford Blue is a little lighter, more muted than Triumphant Navy.
The same difference applies the other way round: Triumphant Navy is a little darker, 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.
See Triumphant Navy on the colour wheel See Oxford Blue on the colour wheel
All matches: Triumphant Navy equivalents · Oxford Blue equivalents