Is there any procedure to sort the assets in DAM by alphabetically while loading the page itself not by filtering options and also the same for site admin pages too.And we're using AEM 6.4 version
Please check https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/aem-6-3-gt-ssort-assets-in...
Sort page in alphabatical order in sites.html (AEM 6.3)
I had written an article to sort Tags in ascending order. You can try something similar for assets. You just need to find out the code that's displaying the assets on the page.