@jmtd, I use a fork of something called rssgen.
You can specify CSS selectors to find blocks for each feeds item, and then you can use Go templates to format them more appropriately. For dates, you can also specify a regex to match the HTML element against (sometimes the date is not in a separate element, so you need to filter it out) and a search and replace map in case the website uses month names in multiple languages.

https://github.com/andrewshadura/rssgen/blob/main/example-config.yaml