Add attributes to implode : i need add to $attr['ids'] array with $gallery_setting.

    function the_featured_image_gallery( $atts = array() ) {
    
        $gallery_setting = get_theme_mod( 'featured_image_gallery' );
    
        if ( is_array( $gallery_setting ) && ! empty( $gallery_setting ) ) {
            $atts['ids'] = implode( ',', $gallery_setting );
    
            echo gallery_shortcode( $atts );
        }
    }

Idealy, i would like:

    echo gallery_shortcode( $atts, array(
      'order'      => 'ASC',
      'size'       => 'full',
      'link'       => 'none'
    ) );

But i know what it does not work. 
Thanks in advance for the help.