Moonpetal vs Faded Red

How close are they?

ΔE 16.1, loose: different enough that you should pick on purpose. Faded Red is a little darker, warmer than Moonpetal.

Can I use Faded Red instead of Moonpetal?

Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Faded Red is a little darker, warmer than Moonpetal.

Can I use Moonpetal instead of Faded Red?

The same difference applies the other way round: Moonpetal is a little lighter, 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.