I have an RT-AC87U, which I'm quite happy with, even though I know it's an older device. I've attempted to configure it to use VLANs, following https://www.snbforums.com/threads/force-lan-port-4-to-use-the-guest-network-for-asus-merlin-rt-ac68u.18969/
However, whenever I try to run a robocfg...