Using Regex how can I check for both special characters and accented letters?

Question

I am new to Regex and I want to create some validation that checks for special characters.

Example:

 const regexSpecialCharacters = /[^a-zA-Z.,-/'()\s]/;

          if (regexSpecialCharacters.test(values)) {
            true
          }

I have this as a base /[^a-zA-Z.,-/'()\s]/ which returns true when there are special characters such as "!" and "?". It also returns true for numbers. It also returns true for accented letters, e.g. è ë however I don't want it to return true for accented letters.

How can I modify the regex to allow accented letters?