When Microsoft Edge first released you couldn't add many other search engines, now over 2 years later the Browser has grown to compete with the big players.
I had previously created a site that will allow you to add Google and other search engines to your Microsoft Edge browser, by all means use it if you want to add other sources but if you're only interested in adding Google search then it's very simple.
All you need to do in order to add Google's search engine to your Microsoft Edge browser is to navigate to google.com and once you have accessed the page (I'm guessing this wouldn't have been the first time) you'll be able to add the search engine through edge by the usual method.
