Sorcerer's Cloak vs Orchid Light

How close are they?

ΔE 18.7, loose: different enough that you should pick on purpose. Orchid Light is noticeably lighter, cooler than Sorcerer's Cloak.

Can I use Orchid Light instead of Sorcerer's Cloak?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 19). Orchid Light is noticeably lighter, cooler than Sorcerer's Cloak.

Can I use Sorcerer's Cloak instead of Orchid Light?

The same difference applies the other way round: Sorcerer's Cloak is noticeably darker, warmer.

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.