Unless I’m missing it, there is no way currently to set the default browse sort order. I remember there was a plugin for it in Omeka Classic.
I checked the Omeka-S settings as well as site settings and theme settings, but didn’t find anything in the UI. Also checked the application files like in /config but didn’t find a setting there.
After some grepping and exploring, I found the setting hardcoded into /application/src/Controller/Site/ItemController.php
public function browseAction()
{
$site = $this->currentSite();
$this->setBrowseDefaults('dcterms:date');
I was able to successfully modify it.
Is there any way to modify this per site without resorting to a plugin? Perhaps I could add a PHP function within the theme associated with this particular site (not root in my case)? I don’t need it to apply to every site at the moment, and of course I don’t prefer to modify the core application code 
The “typical” method of setting default browse orders in Classic was to just include ordering parameters in the link in the navigation.
At this point I wouldn’t mind just manually hard-coding the change from DESC to ASC! If you can point me to where that query exists?
It’s just a particular of our collection at Edison Papers that the order the items were imported in is meaningful, but in ASC rather than DESC. I suppose I could have reversed the import order but as you know our history and how I’ve migrated the data, it’s not a quick and easy option for the 150k records that are already imported.
Oh, the simple solution (didn’t realize “created” was a special term)… we’ve made our “Browse Documents” navigation item link to the following rather than just /item.
/s/digital/item?&sort_by=created&sort_order=asc
When you use sort_by=created, you avoid the additional overhead of a “custom” or “advanced” search which has to join the “value” table to the item+resource tables in order to generate a sort order.