'Accessing' JS elements for use in custom HTML


I’m curious if there’s a way to access particular Plotly visual components for use in custom HTML elements. Specifically, I’d like to access specific marker symbols (eg. circle, triangle) for the creation of a custom HTML legend which articulates which each symbol type represents in the graph.

My specific use case is a restul of my attempt to find a workaround for this issue related to multiple legend support. I was hoping to create a custom html element describing the meaning each symbol type, but am unable to access these symbols in a programmatic way. Any idea if this is possible?