for URL, Image, Media and Gallery controls, you need to extend Elementor\Core\DynamicTags\Data_Tag .
use this code
class Custom_Picture_Tag extends \Elementor\Core\DynamicTags\Data_Tag
{
public function get_categories()
{
return [ \Elementor\Modules\DynamicTags\Module::IMAGE_CATEGORY ];
}
public function get_group()
{
return "additional-data";
}
public function get_title()
{
return "image";
}
public function get_name()
{
return "image";
}
public function get_value( array $options = array() )
{
return [
'id' => 1,
'url' => wp_get_attachment_image_src(1, 'full')[0],
];
}
}