The only anchor-based actions I’ve posted that I know of are in these posts:
- What is the best way to create jump links
- Action to preview anchored headings.
- TOC (auto table of contents) in MultiMarkdown
- Preview with table of contents for MultiMarkdown.
Greg’s transclude actions and my Exploded Markdown Preview action deal with incorporating one draft in the preview of another - which might be an option for some of the earlier section embed functionality that Roam Research is so good at.
But I don’t think that any of these fall into the option to link to a specific section of another draft
However, if I did want to create a link in one draft to a section in another draft, I would write an action that I could trigger using the wiki URL Markup and the Drafts URL scheme (I’m assuming everyone realised that the wiki URL links also support Draft URL scheme links - very useful!! 
) , passing in the UUID of the draft and maybe say the number of the heading (first, second, third, etc.). The action would use the text passed in to load the specified draft into the editor and the navigation marker functions to place the cursor at the correct position.
That would produce something like this for the link, with a comma between the UUID and the position of the navigation marker, and an action called switch.
[[url:drafts://x-callback-url/runAction?text=D245C74F-ED96-4D21-99C6-1F7821EC31B1,5&action=switch]]
And something like this for the action:
- Example: switch
Not exactly the prettiest URL, but functional. While the position of the desired navigation marker against it’s other markers is simply expedient as a demonstration, you could actually search for the navigation marker by its label too.
I’m not sure I’d favour it over adding in unique IDs at key locations as referenced above, as the “clutter” one could argue is presented by adding such unique ID’s I would say is equally as cluttered in terms of the readability and length of the URL needed to take the approach I’ve just set out.