Azure AD B2C translation of custom HTML elements

I'm using Azure AD B2C custom UI and I'm wondering if it is possible to use the translation of own HTML elements

Here is an example:

<hr />
<h3 class="text-center" id="Custom1SignUpNewAccountMessage>Sign up with a new account</h3>
<div id="api" data-name="SelfAsserted">
</div>

I can see the text "Sign up with a new account". Now I would like to translate it for different languages because at the moment it is fixed.

I used the JSON from DefaultLocalizedResources.

"LocalizedStrings": [
{
   "ElementType": "UxElement",
   "ElementId": null,
   "StringId": "Custom1SignUpNewAccountMessage",
   "Override": true,
   "Value": "Hier neuen Acount registrieren!!!"
 },

Unfortunately, Custom1SignUpNewAccountMessage is not a valid element.

Is it possible to do translation "outside" <div id="api" ...>?