Well, I don’t use Zotero or Word so my workflow may be a bit different (and probably somewhat idiosyncratic). I manage my references in BibDesk, which creates and maintains a bib file. But as far as I know, the very same can be achieved by a Zotero library with betterbibdesk.
I do use the Pandoc-style markdown citations (simply [@citekey]) because I write my final drafts in latex. When I have a first draft ready that I wrote in Obsidian, then I export it to latex via pandoc. This way, all my Pandoc-style markdown citations end up as properly formatted latex citations, which then I can compile with my latex compiler. (Or, if I have to send the piece to some colleague who doesn’t use latex, I can export it to Word, etc., with the same result.)
So my setup may require this specific workflow. But I just set up the citations plugin to generate literature notes with the file name of @citekey; this way, first of all, it is easy to tell if something is a literature note, and second, it allows me to enter lit note links as if they were citations, with an extra pair of [ ] added.
For your problem, I’m not sure I understand. If you have a note about a reference already, then could you just set up the Citations literature note file name in such a way that it would take you directly to the already existing note? In that case, it would not create a new one. The doability of this may depend on the naming scheme for your literature notes that are not created with the plugin.