yes you can migrate to an attribute and to appear there, you can use CKEditor Widget and the below is the link:
once you download you can see tow widgets Editor and viewer.
once you click the source you can see the HTML tags there :
now if you have that HTML as a string you can view it throught the viewer one .
hope that is the answer for your question .
In additional to Ahmed’s answer, you can also look at embedding HTML directly into your page using the HTMLSnippet from the Marketplace.
Hi, if the data is exported in valid html, it could be an idea to add some tags to the top and bottom to make it a valid XML file.
XML can easely be imported in mendix by a mapping.