Consider the following: a user has a site on Wix, but wants to use a third-party service to provide translations (the why is not relevant now, suffice it to say that Wix Multilingual is not an option for this user). This service acts as a proxy in front of Wix, and proxies the original website on a different URL.
You cannot modify the URL in any external method to achieve something like:
youtwebsite.com/me-gustan-las-manzanas
You could try to build a whole new website for the translated version in Wix or external platform to achieve this but your domain will cause some problems. One domain can only be connected to one site.