Separate no internet network

I need to create separate guest network that will allow to connect to Guest LAN devices without any internet connection. This is needed to make my printers and other shady wireless devices to work properly but not do anything on internet.

I already have 2,4 GHz guest network, I can configure it as “printer” network, but it is better to create totally separate 2,4 GHz guest network (additional)

Puli device.

How do you use the printer then?

So when you want to use the printer, connect your pc to the guest wifi which has no Internet, print something and then connect back to your private wifi?

This is not good.

What if just block Internet access of the printer.

Something like this

Or maybe block internet via printers MACs (I know them)?

Just connect Printer to your normal wifi and block it access the Internet.

So LAN connection will still work? This toggle blocks WAN? Or LAN too?

Sorry it blocks LAN too.

Maybe use guest wifi. Then in firewall, remove forward from guest wifii to WAN.

Can you show screenshot? It is in LuCi, right?

Solution 1: Use guest wifi and remove guest wifi data forward to WAN.

Go to Luci->network->firewall and remove this one.

Solution 2: Parental control

Use private wifi and enable parental control.
Create an IoT profile, add the printer, and disable Internet access.