On Twitter, Google’s John Mueller said that accents in URLs work fine with Google. However, some tools (and maybe other search engines) might not work with them.
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) 23. März 2019
You can check this in Google’s search results
Here’s an image of a web page URL in Google’s search results that contains accents:
The official URL recommendations by Tim Berners-Lee can be found here.
Check your own web pages
Most modern tools can handle accents and other special characters. Some characters are now allowed in URLs and they can break your website. Check your web pages now with the website audit tool in SEOprofiler to make sure that Google and other search engines can index all of your pages: