What theme are you using? What template is used to display your title, index.php or archive.php? Can you show their code?
You can try changing the title with the the_title hook, or prepare it with get_the_title ().
The easy way?
Just use Custom Post Type UI to create custom taxonomies (in your case: SKU, price, variations, short description, and related products).
And for the admin page, use ACF to add meta boxes to your products edit screen.
That's what I did. Then you can concentrate to other matters.
I think you should save this data in post_meta.
These values are part of every single product post and are different in every product.
You can add custom input fields with add_meta_box() function in the hook add_action('add_meta_boxes', 'my_custom_metaboxes'); for example.