ΔE 11.1, fair: the same colour family, but not a straight swap. Replenish Blue is a little darker, more saturated than Royal Robes.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Replenish Blue is a little darker, more saturated than Royal Robes.
The same difference applies the other way round: Royal Robes is a little lighter, more muted.
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 Royal Robes on the colour wheel See Replenish Blue on the colour wheel
All matches: Royal Robes equivalents · Replenish Blue equivalents