No shortcut for 'document statistics' in gedit
The in the GNOME 3 version of Gedit (3.36.2, in Ubuntu 20.04), there is no sensible shortcut for accessing a word count in the current document. It is not listed in the shortcuts. This is not a plugin, it's core functionality.
Please forgive me for taking this opportunity to make a general gripe about the changes to keyboard accessibility in GNOME 3. In old GNOME, and also in Unity, the use of 'traditional' File, Edit, Tools etc menus with alt-key accelerators meant that one could quickly DISCOVER keyboard shortcuts, with no need to consult documentation. In new GNOME, alt-key accelerators have been eliminated from menus (no Alt-F-S options any more, even if you press F10 to open the 'hamburger' menu), and no keyboard accelerators shown in menus even if they exist. Then, there are multiple incomplete sources of information on what keyboard accelerators exist (compare hamburger->'Keyboard Shortcuts' with hamburger->'Help'->'Shortcut Keys', look at the keys listed under 'Tools'). Keyboard shortcuts are also not typically displayed on mouseover of menus/buttons. 'Keyboard discoverability' as a concept has been totally discarded, it seems, which feels like a backward step that penalises frequent users.