When I first started using Edge Insider I only had one account. Now its making me have a work account and my own personal account. Now my icon has a user overlay on it because I have more than one account when I don't want a 'Work' account on my machine.
@knowguy I might have a workaround. If your problem is that it defaults to your work account, on your desktop you should see a shortcut that has a work label on it. If you delete the shortcut, when you open edge you will be signed into your personal account. That is assuming the problem is related to it defaulting to your work account.