(Please search before making a new FR. Merged to here.)
The challenge I see with this is that there is no enforced structure in an Obsidian note. There is nothing definite to edit. YAML for example is just one supported type of formal structure.
How would you propose resolving this? Would a property convention such as YAML need to be enforced? Would it be auto-detected to match the current style the user happens to be using? What if notes have a mixed style, or syntax errors in a subset of the notes?
Even links are stored as Markdown text. Where would this feature decide to add those links? Append? Prepend? Enforced type of structure?
Or are you just proposing a way simply to edit existing ones, and not necessarily add? (Maybe I was wrong to merge these if “edit” and “add” are meant to be distinct?)
Related FR and plugin requests:
Tag-specific, but similar:
https://forum.obsidian.md/t/assign-tag-to-multiple-files/9750
Somewhat related plugin request: