ΔE 44.1, loose: different enough that you should pick on purpose. Blue Wash is noticeably lighter, much more saturated, cooler than Nightroot Shade.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 44). Blue Wash is noticeably lighter, much more saturated, cooler than Nightroot Shade.
The same difference applies the other way round: Nightroot Shade is noticeably darker, much more muted, warmer.
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 Nightroot Shade on the colour wheel See Blue Wash on the colour wheel
All matches: Nightroot Shade equivalents · Blue Wash equivalents