Block games on LAN at specific times

I dont know, but she should really try and be a better parent.

Two other things. 1. Are there methods to set more specific time schedules in AdGuard? 2. What would be a good appliance to run pfSense and AdGuard on?

Any x86 system that can run ProxMox and has two LAN ports. You virtualize pfsense in one VM, and run AdGuard in LXC. Then, in your pfsense, you set the AdGuard IP address as upstream DNS server, and you are done. Or you can install Opnsense on bare metal and run AdGuard in a freebsd jail. Pick your poison.

Honest question: Does it have to be pfSense? I think you mentioned not spending any money earlier. Does that really mean no money being spent at all?

I ask because you could easily accomplish this with a UniFi gateway; an Express if there are no existing AP’s for WiFi. Or, if there are already AP’s, a Cloud Gateway Ultra. I can’t say either are cheap. But they’re not crazy expensive either (and yes, I know that’s subjective). But you have asked what kind of appliance would be good, so I assume you would need to purchase something regardless?

In UniFi, this whole thing would be easy with policy rules, which can run on schedules. And since it would be at the firewall/gateway level, DNS and TTL’s don’t factor in at all. When the scheduled time comes, the connections to the configured apps/games/services would stop. Period. (I find UniFi also has a much more extensive app list than AdGuard)

Something to consider

I know about it, but I find it a bit too simple and not customizable enough, and I can’t test it. They would need to spend some money on hardware, so a UniFi Express wouldn’t be a problem, but I can’t test it before buying.

Unifi products seem to have a fairly high resale value, and you mentioned already one time payments are okay, so maybe try it and resell if it doesn’t work out. Or even returning it if you’re able to test it fast enough, even if there was a restocking fee that would be less hassle than reselling.

Regarding the TTL with the pfsense setup, does pfsense have the ability to restart on schedules? Perhaps something like that could be used to cut off any active sessions and when it comes back online the new rules would be in place.