ΔE 15.6, loose: different enough that you should pick on purpose. Chancellor Blue is a little darker, more muted, warmer than Shadow Thorn.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Chancellor Blue is a little darker, more muted, warmer than Shadow Thorn.
The same difference applies the other way round: Shadow Thorn is a little lighter, more saturated, cooler.
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 Shadow Thorn on the colour wheel See Chancellor Blue on the colour wheel
All matches: Shadow Thorn equivalents · Chancellor Blue equivalents