Here's useful video explaining just that: 

You can manually insert the Divi module using custom PHP code in your child theme’s functions.php.

1. Create a new Divi layout containing the desired module in the Divi Library.
2. Add code in your child theme to call the layout in the sidebar area:

//Divi module in sidebar
add_action('get_sidebar', 'add_divi_module_to_sidebar');
function add_divi_module_to_sidebar() {
    echo do_shortcode('[divi_shortcode]');
}