ΔE 10.5, fair: the same colour family, but not a straight swap. Gorthor Brown is more saturated than IJA #31 Cha Kasshoku (Tea Colour).
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Gorthor Brown is more saturated than IJA #31 Cha Kasshoku (Tea Colour).
The same difference applies the other way round: IJA #31 Cha Kasshoku (Tea Colour) is 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 IJA #31 Cha Kasshoku (Tea Colour) on the colour wheel See Gorthor Brown on the colour wheel
All matches: IJA #31 Cha Kasshoku (Tea Colour) equivalents · Gorthor Brown equivalents