Just redirect to Nitter:

    // ==UserScript==
    // @name        Redirect to Nitter
    // @version     1.0
    // @description Automatically redirect from twitter to nitter
    // @match       *://twitter.com/*
    // @match       *://x.com/*
    // @run-at      document-start
    // ==/UserScript==

    (function() {
        const nitterInstance = 'nitter.poast.org'
        location.href = `https://${nitterInstance}` + location.pathname // + '&' + location.search
    })();