It seems somewhere along the line Edge (claims to be 114.0.1823.67, June 29, 2023) completely removed the option to disable it. I thought it was there previously. I'll have to quit using the darn thing if it keeps sending local network requests or misspellings to DDG. Sad and annoying.
I already added value SearchSuggestEnabled (dword:0) to reg at Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge. No apparent effect.
Aside, but perhaps pertinent, I've also disabled Edge updates in every way mentioned on the interwebs anywhere, and seemed to have finally succeeded only by renaming the Edge Update App folder.