Thanks.
It seems that Onyx tries to standarize a lot on hardware and software, the biggest difference between models being touch screens/digitizers. I read about the old models with RockChip processors.
So, if you want to go through the trouble, you can backup your whole device (without even rooting) or grab a copy of recovery for Magisk using Qualcomm EDL mode. There's a bit of a thread on that here:
https://www.mobileread.com/forums/sh...d.php?t=339471