There currently isn’t anyway to do this in ACF. You could try submitting a feature request here https://support.advancedcustomfields.com/new-ticket.
You might also use the acf/render_field https://www.advancedcustomfields.com/resources/acf-render_field/ hook to add additional controls to the gallery field and then figure out how to add custom javascript to the field to make it work https://www.advancedcustomfields.com/resources/adding-custom-javascript-fields/. Unfortunately, that’s all I can offer because I don’t know exactly how to do this.
