You can slightly alter the script, and make it so that when you <input type="text" id="input"> in the <input type="text" id="input"> field, it duplicates in <input type="text" id="input1"> , but with transliteration. And in <input type="text" id="input"> remained as it is?
$('div#xfield_holder_input1').css('display', 'none'); var input = document.getElementById('input'); input.addEventListener('input', function() { this.value = textTransform(this.value); $('#input1').val($('#input').val()); }); function textTransform(text){ var arrru = [ 'Я','я','Ю','ю','Ч','ч','Ш','ш','Щ','щ','Ж','ж','А','а','Б','б','В','в','Г','г','Д','д','Е','е','Ё','ё','З','з','И','и','Й','й','К','к','Л','л','М','м','Н','н', 'О','о','П','п','Р','р','С','с','Т','т','У','у','Ф','ф','Х','х','Ц','ц','Ы','ы','Ь','ь','Ъ','ъ','Э','э', ' ' ]; var arren = [ 'Ya','ya','Yu','yu','Ch','ch','Sh','sh','Sh','sh','Zh','zh','A','a','B','b','V','v','G','g','D','d','E','e','E','e','Z','z','I','i','J','j','K','k','L','l','M','m','N','n', 'O','o','P','p','R','r','S','s','T','t','U','u','F','f','H','h','C','c','Y','y','`','`','\'','\'','E', 'e', '-' ]; for(var i=0; i<arrru.length; i++){ var reg = new RegExp(arrru[i], 'g'); text = text.replace(reg, arren[i]); } return text; }