Typhon Ash vs Moonstone Grey

How close are they?

ΔE 8.7, close: similar, with a visible difference side by side. Moonstone Grey is a little lighter, more muted than Typhon Ash.

Can I use Moonstone Grey instead of Typhon Ash?

Usually, if you are not matching paint already on the model. Close match (ΔE 9). Moonstone Grey is a little lighter, more muted than Typhon Ash.

Can I use Typhon Ash instead of Moonstone Grey?

The same difference applies the other way round: Typhon Ash is a little darker, 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.