Looking at the screenshot that section does accept a dynamic source so you could wire up a metafield definition to the multiline type and in that put your html.
That would be per product though and not template level solution if you need the same text for all products.
https://help.shopify.com/en/manual/metafields/metafield-definitions
https://help.shopify.com/en/manual/metafields/displaying-metafields-on-your-online-store
If you need to hire help to set that up contact me with store details for pricing, email in my signature.