Does the D8 version work with Varnish?

@darrenwh please read Smart IP page under the "Configuration / Cache Performance Note".

Am I blind, or does that section no longer exist? I, too, would like to know how to get this running behind Varnish or nginx

EU Cookie Compliance checks location using JS, and that works with Varnish or db caching. As far as I can see the module will not work reliably with a cached request so an uncached Ajax request to check location makes sense.

Drupal 8 & 9 are no longer supported. This version of the module this was opened against only supports these earlier versions of Drupal. If this is still something you want addressed in the current 5.x version of the module, please update and provide some next steps.