Directly in the codex, the “Devilish Aspect” has the following description:
After generating 100 Fury your next direct damage creates Dust Devils that deal X damage.
When imprinted, the same aspect has the following description:
After generating 100 Fury your next direct damage creates 2 Dust Devils that deal X damage to enemies along their path.
After generating 100 Fury, the buff tooltip has the following description:
Your next Core Skill will spawn a Dust Devil.
The tooltip description therefore refers to core skills, whereas the codex/imprinted descriptions refer to any direct damage. As the effect is actually triggered by any direct damage and spawns 2 dust devils, please fix the tooltip description.