I would like to contribute by leaving a code to change the style

In my case I didn’t want the label to be a 1, I wanted it to be a symbol for ? so the first thing we will do is to implement this JS

document.addEventListener('DOMContentLoaded', function() {
    // Select the <sup> elements to modify the number.
    const footnoteNumbers = document.querySelectorAll('.easy-footnote a sup');

    // Changes the content to the question mark symbol
    footnoteNumbers.forEach(function(footnote) {
        footnote.innerText = '?'; // this one to avoid duplicates
    });
});

Then we can fix it with some css, in my case the symbol was duplicated, but with this code it is solved.

/* This CSS block adds a symbol after the link */.easy-footnote a::after {
    content: ''; /* Leave empty to remove the extra symbol */
}