Google's John Mueller said on Twitter that having URLs with accents are perfectly fine for Google. John said "Accents in URLs are no problem -- feel free to use them."
He did warn that sometimes your own internal tools or third party tools have issues with tracking them. "You sometimes need to watch out for how your own tools work with them, but I suspect most of them will just work fine too," he added. But from a Google perspective they do work.
Here is a URL in Google's search results with accents in them showing up fine in search:
See what I did there? :)
Google previously said that Cyrillic script and those special characters and/or accent marks on characters work fine for Google. So this is just reinforcing that statement from 2017.
Here is John's tweet:
Accents in URLs are no problem -- feel free to use them! You sometimes need to watch out for how your own tools work with them, but I suspect most of them will just work fine too.
— 🍌 John 🍌 (@JohnMu) March 23, 2019
They seem to also work fine in Bing, if you are curious.
Forum discussion at Twitter.