ΔE 10.0, close: similar, with a visible difference side by side. Alien Purple is a little lighter than Translucent Purple.
Usually, if you are not matching paint already on the model. Close match (ΔE 10). Alien Purple is a little lighter than Translucent Purple.
The same difference applies the other way round: Translucent Purple is a little darker.
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 Translucent Purple on the colour wheel See Alien Purple on the colour wheel
All matches: Translucent Purple equivalents · Alien Purple equivalents