Is it possible to have different URLs for variants

Hi,

Yes, you can use that URL:
www.mysite.com/XXX-product-20-cm
where XXX is the id of the variant.
As long as the id of the variant is added at the beginning of the URL, you can put whatever you want after it and it will display the product page with the variant preselected.

Hi,

Sorry for the delay, your post wasn't showing to us for some reason.

The construction of SEF URLs is more complex than that.
A SEF URL of a product page will look like this:

The [parent menu item alias] and [menu item alias] parts of the URL are added based on the menu item you're on.
If your menu item is directly under the root menu item, then you won't have a parent menu item alias in the URL.
And if your menu item is the default menu item of your website (the homepage), then you won't have the menu item alias in the URL.
The [product SEF name] comes from the HikaShop SEF configuration. This can be emptied, modified, etc.
The [product id] is usually the product ID but the variant DI can be used too. And if you have the "remove category and product ids from URLs" setting activated, that parameter can be removed (but it can still be there).
The [product alias] is the alias of the product. If not specified, the system will try to use the product name, but it can sometimes create problems, when the product name has special characters in it (not english letters).
The [.html] comes from Joomla and depends on how you configured the Joomla SEF settings in the Joomla configuration.

But it's actually quite easy to get a variant URL without trying to construct it. Go on the product page, add the variant you want to the cart, and in the checkout cart view, the link to the product page will actually use the variant ID, so you can use that link.