Hi, I just found something that may help some of you.
Originally, I had a similar problem: business cards scanned with (latest IOS version as of today) Scannable are not editable in Windows 10 desktop Evernote (also latest as of today). Pretty dumb, i thought, given that I remember the same problem from about 1-2 years ago.
Anyway, one workaround is to actually open the business card saved on the desktop by double clicking it. Edits done there seem to work all right. I'm still currently testing, but it looks like it's doing the trick.
Hope this helps!