[wldcordeiro]

You can do that in Firefox and with more granular control. If you right click in a search box you can choose to "Add a keyword for this search" and then you can make the keyword whatever you choose.

For example: I have a folder in my bookmarks containing like Youtube which is this url https://www.youtube.com/results?search_query=%s&oq=&gs_l= associated with the keyword "yt" so I can type yt <search term> and it loads the Youtube results. I've also added one for the Mozilla Developer Network (mdn <search term>), Python Documentation (py2 <term> or py3 <term>) and I add others as I use them more.

[gpvos]

I use that, but it isn't as good as it used to be in Opera. Opera auto-completed your search using the target search engine's autocompletion. I don't use Chrome often enough to know if it does that too, but it might make me switch. (I switched from Opera to Firefox because of the plugin ecosystem.)

[kretor]

Chrome has all those features too, it let's you add search engines via right-clicking a searchbox, ,you can change the search keyword, and "<search-keyword> <search-terms>" in the omnibar works as described by you.