Addendum:

> there are apparently further PPC476FP-based SoCs, which somehow went
> under my radar for years.

Another one from 2017/2018 (800 MHz dual-core):

https://en.wikipedia.org/wiki/NeuroMatrix#Overview
https://www.module.ru/uploads/media/general-6418bc17a7.pdf (page 7)
https://lists.debian.org/debian-powerpc/2020/05/msg00153.html