modeling - How do I create a vertex at the intersecting point of two intersecting edges without addon or scripts, no faces involved? - Blender Stack Exchange
vertex point at intersection - Modeling - Blender Artists Community
modeling - How can I add vertices to intersection of two edges? - Blender Stack Exchange
Vertex at intersection? - Modeling - Blender Artists Community
Checking for overlapping
Merge Edges at Intersection – Blender Knowledgebase