ΔE 13.0, fair: the same colour family, but not a straight swap. Forest Sprite is noticeably darker than Faded Green. They are different kinds of paint: AMMO by Mig Faded Green is an opaque base/layer paint and Army Painter Forest Sprite is a one-coat contrast-style paint, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 13). Forest Sprite is noticeably darker than Faded Green. They are different kinds of paint.
The same difference applies the other way round: Faded Green is noticeably 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.
See Faded Green on the colour wheel See Forest Sprite on the colour wheel
All matches: Faded Green equivalents · Forest Sprite equivalents