Interaction layer trigger scroll above not working as expected

No, it’s working correctly, trigger using absolute values, not relative values. For relative values and more advanced scroll features, we have Animation addon which uses GSAP under the hood. And it has options for scroll calculation based on object instead of window and it has also Observer type which can be attached, for example, for scrolling up direction.

If you use Greenshift theme and you need to enable sticky header, then you don’t need Interaction layer, because header block has sticky option