When I send a link in chat or whisper twitch does not render a preview for a link like other social media platforms do. Twitch does not support previews for links or metatags for Twtich are different?
This is correct.
First party doesn’t do link previews for anything except clips, to my knowledge
That would be a uservoice suggestion - https://twitch.uservoice.com/
This forum deals with third party support.