ΔE 23.7, loose: different enough that you should pick on purpose. Faded Purple is noticeably darker, much more muted, warmer than Dechala Lilac.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 24). Faded Purple is noticeably darker, much more muted, warmer than Dechala Lilac.
The same difference applies the other way round: Dechala Lilac is noticeably lighter, much more saturated, cooler.
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 Dechala Lilac on the colour wheel See Faded Purple on the colour wheel
All matches: Dechala Lilac equivalents · Faded Purple equivalents