ΔE 10.5, fair: the same colour family, but not a straight swap. Ionrach Skin is a little darker than Leopard Stone Skin.
Can I use Ionrach Skin instead of Leopard Stone Skin?
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 10). Ionrach Skin is a little darker than Leopard Stone Skin.
Can I use Leopard Stone Skin instead of Ionrach Skin?
The same difference applies the other way round: Leopard Stone Skin is a little lighter.
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.