NextCloud library on SharePoint

I’m working on an implementation of a NextCloud solution for a customer and ran into a question from them which I can’t find any good answers for and thought that someone here might know if it’s possible.

The reason for them to switch from SharePoint to NextCloud is due to GDPR so they will instead host their high-risk files on their own hosted NC server.

What they wondered however is if there’s any way of using the NC server as the storage and show the file library on SP. Not sync the files to SP, just show the library and being able to view the files from SP.

I don’t know if this is possible or even an actually smart move to make but I thought I would at least ask the people here who might actually know something if the possibility exists.