ajimix Assuming your browser multibar is your main entry into the search engine, the best solution i have found so far is to define a custom bang that in the normal use-case simply points to https://kagi.com/search?q=%s call it e.g. "!fallback"
You can create the bang here:
https://kagi.com/settings?p=custom_bangs_form
Make your kagi search engine configuration point to "https://kagi.com/search?q=!fallback %s", which basically means you will always use this bang for every single query. Because the custom bang is pointed to kagi.com, it will redirect to kagi.com without the search query and search as normal. This will not count double towards your query count (bangs generally don't).
Now, when you finally reach your search limit, simply change the !fallback bang to something like "https://duckduckgo.com?q=%s".
Because every single query done from your multibar always uses this !fallback bang, you will now automatically always search duckduckgo in an account-wide manner. Unfortunately, the switch back to kagi will not be automatic, so you will need to add a calendar reminder to do this at the beginning of your new period.
Note that because bangs are resolved recursively, this does not break compatibility with other bangs. E.g. "!fallback !ddg !bing test" will resolve just fine and end up searching "test" in bing. Bing will not resolve it further, so in !bing the bangs still go boom š
