On 4/23/19 Oculus integration 1.36 was released with this note:
The Oculus Integration for Unity (not including the Avatars components) has been updated to support ARM64 development
Three months later and Oculus Avatars still don't support ARM64. If you do an ARM64 build of an Oculus Quest project in Unity (2019.1, Oculus integration 1.38) all avatar components disappear. What's the timeline for adding ARM64 support to Avatars?
Looks like today's Oculus integration 1.39 adds Android64/libovravatarloader. Haven't had a chance to test on device yet, but this appears to be resolved. (woot.)
Builiding an ARM64 Unity app with Oculus Avatars still doesn't appear to work. When my app finishes launching I get thrown to a dialog box that reads "Update In Progress" "Please leave your device on, connected to Wi-Fi and plugged into a power source until the updates finishes."
I just did a build with Oculus Integration 1.40 from the Unity Asset Store (and whatever Quest update auto-installed earlier this week) and Oculus Avatars are working in ARM64 Quest builds.