I know it’s not exactly what you are asking, but on kagi.com you can increase & decrease weighting of any domain in search results. You can also create custom url redirects, which could work for cases where the url contains the same information but on another domain (i.e. redirect youtube result to same video ID on piped).
But I’m not sure if kagi fits your needs, while it is privacy focused it is a commercial product and it asks a monthly subscription fee
I know it’s not exactly what you are asking, but on kagi.com you can increase & decrease weighting of any domain in search results. You can also create custom url redirects, which could work for cases where the url contains the same information but on another domain (i.e. redirect youtube result to same video ID on piped).
But I’m not sure if kagi fits your needs, while it is privacy focused it is a commercial product and it asks a monthly subscription fee