Guest WLAN on stupid AP?

[eduperez]

Ok, I think I have a better picture of your setup now. Have a look at this thread, where I guided someone else with a similar need:

Help With Tagging from Router to Dumb AP

I am comfortable creating Dumb Access Points using THIS article. I am comfortable creating WLANs for Guest Devices and IOT Devices using THIS article. My goal is to introduce a Mikrotik RB750Gr3 flashed to OpenWRT, to my current home network. This new Mikrotik Router would be connected to the internet, and all Access Points and un-managed switches in my house would connect to the Mikrotik. I'm sure I could setup my Guest Devices and IOT Devices WLANs again on the new Mikrotik router, just with…