Create text boxes in a matrix question for respondents who select "other"

You can use this JS:
Qualtrics.SurveyEngine.addOnReady(function () {
    document.querySelectorAll("td.last").forEach((item) => {
        let sl = item.querySelector("[type='radio']");
        item.querySelectorAll("*").forEach((child) => child.hide());
        item.insertAdjacentHTML(
            "afterbegin",
            ""
        );
        document.querySelector("#other_text_" + sl.name.split("~")[2]).oninput = function (e) {
            if (e.target.value.trim() !== "") sl.checked = true;
        };
    });
    document.querySelector("#NextButton").onclick = function () {
        document.querySelectorAll("[id^='other_text_']").forEach((tb) => {
            Qualtrics.SurveyEngine.setEmbeddedData(tb.id, tb.value);
        });
    };
});
You'll need to create ED for each choice like other_text_1, other_text_2 etc.