How to customize the text in an embedded post?

I struggle to understand why there is not an option to customize the full embedded text. I do not want to scrape any actual content from the embedded URL, instead just have a link to it with a short description (e.g. just the meta summary).

Right now I do this with an automated API call, but want to switch to the native embedding feature.

I tried creating a hidden element on the scraped site specifially for Discourse to scrape just that single element, but the downside is that the onebox will not be displayed for the link.

Customizing the embed.imported_from also has its limitations, since it’s always forced into a <small> tag allowing no actual customization.