You can do this in firefox, too, but it's quite hidden and doesn't have a nice UI. Bookmarks can have keywords associated with them in the bookmarks editor, so you can add a "Bing" bookmark with URL "https://bing.com/?q=%s" and Keyword "bing". It'll work, but the "bing" prefix won't be highlighted as it is in Chrome when using it to do a search.
The "Add a keyword for this search" context menu option automates creation of this bookmark, but you can also do it manually if firefox doesn't recognize a search field or something like that
It is quite "highlighted": after typing exact keyword it is the first suggestion below URL bar and after typing space and some query it reflects this by displaying "domain.tld: query" there, seams good enough to me.
The "Add a keyword for this search" context menu option automates creation of this bookmark, but you can also do it manually if firefox doesn't recognize a search field or something like that