JReferences
This plugin adds references and citations functionalities (in a wikipedia-like style).
Plugin Tag: footnotes
Advanced Footnotes
Advanced Footnotes lets you add footnotes on articles via shortcodes.
Footnote Drawer
Footnote Drawer displays footnotes in the drawer UI.
Icon Footnote
Gutemberg block that adds beautiful footnotes using material icons..
MNML Footnotes
Simple auto-listed footnotes for posts.