Hi there, root can't be officially supported for obivous reasons. I can't help you with that, but i'll keep this thread open so that users can help you and talk about it
Just to know, would it be thinkable to include in the ROM some build-in firewall (like afwall+) (within the system, with the good right, there's no need to get root), or is it forbidden by android license / impossible to make ? That would be a huge commercial advantage for your phones.
Btw, i just got my 6800 pro, and for now i'm really happy about it !
Magisk is the best option imho. You just need to flash a boot image modified by Magisk Manager. No modification of the recovery or system partitions : easy OTA updates.
Short version :
Extract Boot Image with SP Flash Tool (version 5.1828 works fine)
Copy boot image to your BV6800 Pro.
In Magisk Manager, press Install > Install > Patch Boot Image File, and select your stock boot image file
Magisk Manager will now patch your boot image, and store it in [Internal Storage]/Download/patched_boot.img
Copy the patched boot image to your PC.
Flash the patched boot image with SP Flash Tool to your device and reboot. The phone will reboot twice, don't panic.
Enjoy root
I'll update this to a detailed version when I have time.
Yes. Just follow this procedure. Sorry I don't have time to write a super detailed one but you only need to search this forum for SP Flash Tool and how to use it (install drivers, extract boot, reflash boot).