If you can add a !bang feature like duckduckgo it will be great. For example if i want to check if a website is authentic or scam, I should be able to do so by just adding !scam at the start of my search and it should just search my keyword on notscam.com. similarly !wiki should search on wikipedia and !nf on netflix? duckduckgo has this functionality which is really handy. any site can be assigned a !keyword.
If you are sending these queries to a default search engine that supports those bang shortcuts (such as DDG or Brave Search), it will work by using that search engine.
But if you mean specifying your own shortcuts directly in the browser, you can do this now by right-clicking the URL bar and selecting “Manage search engines.” Then create a new ‘search engine’ by clicking ‘Add.’