Hey, @maurofon!
This happens because on classic themes, the short description is on a specific block called “short description”, but on FSE themes, the short description is on a post excerpt block, which only displays text.
We have a website where you can submit feature requests and upvote the ones other people submitted and you like. So if you wish, you can submit a feature request to change that so the block allows HTML on it. You can check that out here.
We appreciate your suggestions and are always looking for ways to improve our products and services, and input from users like you is invaluable.
Regarding a short term solution, you might be able to achieve that with custom code. While we can’t provide support for code customization as per our support policy, we do our best to offer advice and direct you to appropriate resources.
You can visit the WooCommerce Facebook group or the #developers
channel of the WooCommerce Community Slack. We’re lucky to have a great community of open-source developers for WooCommerce, and many of our developers hang out there too.
Please let us know if there’s anything else we can do to help or if you have further questions.
Have a wonderful day!