Load balancing Lan clients

Is this even possible? I purchased the router pre installed. I don't think PandoraBox is active anymore because when I go to "system/software/update lists" there is no connection to the lists download feature...

Downloading http://downloads.pangubox.com:6380/pandorabox/18.07/targets/ralink/mt7620/packages/Packages.gz
*** Failed to download the package list from http://downloads.pangubox.com:6380/pandorabox/18.07/targets/ralink/mt7620/packages/Packages.gz

The platform is identical to official openwrt so the question is there a rule or policy that can be enforced so that a new connection to an internet server is routed to the "least active" WAN connection/interface?