There are a couple of basically equivalent approaches, but here's an easy one: http://pages.vaneckdemos.com/Form-Disclaimer-from-Token.html
The LP contains this bit of code (in an HTML block):
<script>
MktoForms2.whenReady(function(form){
var formEl = form.getFormElem()[0],
replaceableEls = formEl.querySelectorAll('[data-replace-with]');
Array.prototype.forEach.call(replaceableEls, function(el) {
replacementEl = document.querySelector('#'+el.getAttribute('data-replace-with'));
el.parentNode.replaceChild( replacementEl, el );
replacementEl.removeAttribute('style');
});
});
</script>
This is the disclaimer on the LP with the token:
And this is the Rich Text area on the form:
Note the code allows you to have unlimited pairs of data-replace-with and replacement elements.
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