Not showing ‘Pin It’ button on shortcode images

Hello! I’d love to use this plugin but I would not want the ‘Pin It’ button to show on all images. I know there’s a way to disable it by adding the additional ‘nopin’ class, but unfortunately I’m using another plugin that uses shortcode and it’s not possible to add additional class for shortcode. Thus, I’m wondering if there was a way round this. Is there any additional CSS that would disable the ‘Pin It’ button on all images? Then hopefully this would stop the shortcode images from showing the button and I could manually add it only on certain images.

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