See my comment about using it with uBlacklist, which does exactly that. By default it is configured only for google search but you can enable other search engines in the options.
There’s instructions and an instruction video in the link for adding to uBlock Origin Firefox extension. Also says uBlacklist (Firefox and chrome extensions), PiHole(raspberry pi set up to filter traffic on your network), or AdGuard(browser extension and app).
You can probably implement with a router blacklist if your router supports that but that’s beyond my knowledge
Nah. It's easier to just blacklist individual users here. People who, say, consistently produce AI content or who reply with nonsense like "guess you should blacklist lemmy too" because they mistakenly believe they sound clever.