egs-to-steam.user.js

// ==UserScript==
// @name         My EGS games
// @namespace    https://gist.github.com/ntnbrtnkv
// @version      0.1
// @description  Export epic games store games/translactions
// @author       ntnbrtnkv
// @match        *://www.epicgames.com/account/transactions*
// @grant        GM_setClipboard
// ==/UserScript==

(function() {
    "use strict";

    const loadMoreQ = '#payment-history-show-more-button';
    const transactionListQ = 'table';
    const transactionQ = 'tbody tr td:nth-child(2)';
    const sheetsURL = 'https://docs.google.com/spreadsheets/d/1eWZcEebfS8CxV4CtKwzmir08mI5Z6xs6Ll7DyHllD5Q/edit#gid=0';

    function doExport() {
        const btn = document.querySelector(loadMoreQ);
        if (btn) {
            btn.click();
            setTimeout(doExport, 3000);
            return;
        }

        const trs = document.querySelector(transactionListQ).querySelectorAll(transactionQ);

        const list = [...trs].map(e => e.textContent);
        GM_setClipboard(list.join('\n'))
        window.open(sheetsURL, '_blank').focus();
    }

    function addButton() {
        const transactionListEl = document.querySelector(transactionListQ);

        if (!transactionListEl) {
            setTimeout(addButton, 1000);
        }

        const buttonsContainerEl = transactionListEl.parentElement.nextSibling;

        const btn = buttonsContainerEl.firstChild.cloneNode();
        btn.id = '';
        btn.innerText = 'Export all';
        btn.onclick = doExport;

        buttonsContainerEl.appendChild(btn);
    }

    addButton();

})();