How different are two people of the same type with different instinctual variants?

Dramatically different. A self-preservation Type 6 focuses on practical safety; a sexual Type 6 craves intense connection; a social Type 6 seeks group belonging. The core fear is the same, but how it manifests in relationships is entirely distinct.

Do instinctual variants affect attraction patterns?

Heavily. Sexual variants are drawn to intensity and chemistry; self-preservation variants prioritize stability and comfort; social variants seek shared groups and values. This explains why two people with the same MBTI and Enneagram type might pursue completely different partner qualities.

Can couples with different dominant instincts make it work?

Yes, but they'll need to understand their different priorities. A self-preservation Type 3 wanting financial security with a sexual Type 3 wanting adventure requires explicit conversation about values. Understanding the instinct clarifies what's really driving the apparent conflict.