If I understand you correctly, Pandoc Reference List is the plugin that you need.
It “renders” a pandoc-style citation [@citekey] as a human-friendly Authors et al., YYYY format. I mean, it only changes how [@citekey] looks, and it does not change the actual citation format (which is good for future proofness and portability, as this pandoc style is the de-facto standard).
I’m not sure why this feature is not mentioned in README.