Mouthing problem?

[taniaa001]

Hi Guys,
I need advice. I go this this park called pooch park and I take my 7 month old GSD. I am really starting to hate it

Misha is the type of dog that LOVES to play, I will admit that she is rough. People don't like when she mouths their dog.
I have had many fights with people where they say she is ripping the skin off their dog
She loves to play that way, She barks at the dog and paws them. She is not aggressive but the people are and so it makes me protective of her.
People have suggested I muzzle her or use an anti barking collar. I am not fond of the collar because it zaps the dog.

Is this a big problem? How can I stop this?
I need advice please