Magento 2 system variable for "Order Created at" for email templates

Question

What is the email template system variable for "Order Created at" for Magento ver. 2.2.6?

Using the variable name: {{var order.getCreatedAtFormated('long')}} doesn't work for me. This is a variable applied using the Magento UI:

I looked into the devdocs and the is no variable for this: https://devdocs.magento.com/guides/v2.2/frontend-dev-guide/templates/template-email.html

In addition, why are the varibale names different from when you using Magento UI and when looking at the devdocs? E.g:

Getting billing address:

1. Using UI: {{var order.getBillingAddress().format('html')}}
2. Devdocs: {{var formattedBillingAddress|raw}}

NOTE: I had to use the devdocs variable names for it to work properly.

Answer 1

Use :

{{var order.getCreatedAtFormatted(2)|raw}}

Answer 2

You can either set is_legacy column in email_template table to 1

or use {{var created_at_formatted}} variable instead (but it doesn't available for shipping, creditmemo and invoice emails)

The reason is that Magento\Framework\Filter\VariableResolverStrictResolver\StrictResolver doesn't provide handleObjectMethod() method (and Magento\Framework\Filter\VariableResolver\LegacyResolver does)