ΔE 18.3, loose: different enough that you should pick on purpose. Ember Orange is more muted than Trollslayer Orange.
Can I use Ember Orange instead of Trollslayer Orange?
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 18). Ember Orange is more muted than Trollslayer Orange.
Can I use Trollslayer Orange instead of Ember Orange?
The same difference applies the other way round: Trollslayer Orange is more saturated.
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.