I had covered setting up the Ubiquiti UniFi USG with IPv6 in a previous article. I recently had someone ask me about the EdgeRouter Lite setup and having issues, so I decided to pull mine out of storage and try it out.
The good news is, if you follow the guide starting at Chapter 3 using the Basic Wizard, it all just works! I was using EdgeRouter Lite version 1.9.1.
Using Setup Wizards – Basic Setup
Enable DHCPv6 PD and leave the default settings. It should look like this in the setup:

With that, you will will be assigned a /128 for your router and be assigned a /56 address space. The EdgeRouter will pull a /64 for each of of the LANs for assignment to your devices from that /56.

