JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <input type="hidden" value="" name="participants[1][canceled_one]" />
    <input type="hidden" value="" name="participants[2][canceled_one]" />
    <input type="hidden" value="" name="participants[3][canceled_one]" />
</div>
<div>
    <input type="hidden" value="" name="participants[1][canceled_two]" />
    <input type="hidden" value="" name="participants[2][canceled_two]" />
    <input type="hidden" value="" name="participants[3][canceled_two]" />
</div>

JavaScript

$(':hidden[name^="participants["][name$="][canceled_one]"]').prop('type', 'text').val('one');

$(':hidden').filter(function() {
    return /^participants\[\d+\]\[canceled_two\]$/.test(this.name);
}).prop('type', 'text').val('two');