Hi,
Removing the component/hikashop part of the URLs won't help avoid the duplicate link content.
But the fact that it adds the itemid parameter instead of removing the component/hikashop part is because the id that you entered isn't for a menu item of the type HikaShop but from another component.
The solution here will be to enter the URL of the product page in the canonical URL field of the products. And when you translate the products, you'll also find a canonical URL field so that you can enter the URL for each language for the product.
Then, it will prevent the duplicate content SEO errors, regardless of what is the current URL of the product page.
And if you turn on the "force canonical URLs on listings" setting of the HikaShop configuration, you'll even get always the same URL for the product pages, regardless from where you're coming.