Link previews happen if you hold click on a link or choose it in the right click menu. By default it shows pretty much just the title of the page and a banner asking you to enable ai summaries.
It's kinda annoying, but not because of the ai. And you can easily disable it
If you want to send files between just your own devices KDE Connect is great and can do many other things too. If you are on Gnome there is a gnome extension for better integration (gsconnect I think?)