[NetBSD 9.0 available!]
(http://blog.netbsd.org/tnf/entry/netbsd_9_0_available)
The first release with support for NetBSD/aarch64 was NetBSD 9.0 on February 14th, 2020.
https://www.netbsd.org/releases/formal-9/NetBSD-9.0.html
- Amlogic Meson-GXBB, and Meson-GXL https://wiki.netbsd.org/ports/aarch64/