If the "/nl" was added through WPML, there's no way to keep it if you uninstall WPML.
If you however migrate the whole website to this directory "/nl" (create a directory on your hosting called "nl", right in the folder that's connected to your domain), then WordPress itself will be installed in the "nl" directory and in that way, you could keep the same format.
Here is a small tutorial on how to use Duplicator: hidden link
I would personally prefer to just show the domain without anything coming after but if that's what you want, that's how you can do it. However, this falls out of the purpose of our Support Policy and is not necessarily related to WPML ๐
I hope that you will find all this information helpful!
Good luck with the website.
Kind regards,
Mihai Apetrei
This ticket is now closed. If you're a WPML client and need related help, please open a new support ticket.