ΔE 11.7, fair: the same colour family, but not a straight swap. Medium Grey Blue is noticeably darker than Phantom Blue.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 12). Medium Grey Blue is noticeably darker than Phantom Blue.
The same difference applies the other way round: Phantom Blue is noticeably 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 Phantom Blue on the colour wheel See Medium Grey Blue on the colour wheel
All matches: Phantom Blue equivalents · Medium Grey Blue equivalents