When you make a normal ‘link’ post, if the url ends with .mp3 then PieFed will provide audio player controls on the page and put a little speaker icon on the post teaser, shown in lists of posts.
Go to https://piefed.social/post/44964 to see it in action.
Wow, yeah that would be cool. There is a lot of German and Portuguese content on the threadverse… Check out all these Brazilian communities - https://piefed.social/communities?search=eco.br