I would expect the Analytics Snippet module to work… similarly to other analytics solution, Plausible just needs to to make sure its javascript snippet is loaded on all pages.
An alternative solution, which is the one I used, is to add the snippet directly in the theme. Just before </head> in the file /view/layout/layout.phtml of your theme should work (make sure to do this for all of your themes if you use more than one).
Works with the module! Thanks, I have very limited skills with editing the theme. So I am trying to stay away from that. If you know how to add a banner image to a site using the CSS editor let me know;)