Gnome Cheeks vs Bright Brown Grey

How close are they?

ΔE 7.8, close: similar, with a visible difference side by side. Bright Brown Grey is more muted than Gnome Cheeks.

Can I use Bright Brown Grey instead of Gnome Cheeks?

Usually, if you are not matching paint already on the model. Close match (ΔE 8). Bright Brown Grey is more muted than Gnome Cheeks.

Can I use Gnome Cheeks instead of Bright Brown Grey?

The same difference applies the other way round: Gnome Cheeks is more saturated.

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.