Changing Search Provider in Edge

In Edge, click the 3 dots in the upper-right of the window

Then click "Settings" on the menu that comes up

In the left sidebar of the page that is opened, click "Privacy,search,and services"

On the page that opens, scroll down until you see "Address bar and search" (should be close to the bottom).  Click that option

On the next page, you can choose you provider of choice in the "Search engine used in the address bar" drop-down box

Selecting "Address bar" from the "Search on new tabs uses search box or address bar" drop-down will set the search box on new tabs to use you selected provider.