I have a muzzle in my gear....just in case and I do use it for nail trims on two of my dogs that hate having their nails done. I muzzle all my dogs at the vet, just because the vet feels more comfortable and I know two of my dogs would bite because they don't want their space invaded.
Basket muzzles are the only ones that allow drinking and panting. I would work with her in public so you don't have to think about muzzling her when you are out and about...much different scenario than a vet office with all the smells. Dogs can scent stress and it manifests in those environments.
The book Control Unleashed by Leslie McDevitt
has exercises to help handlers manage reactive dogs.
Keep a vigilant eye on situations and you should be able to manage interactions with Emma, set her up to succeed and her confidence level high.