query posts across a network

I would like to create a featured post carousel with posts from across the entire network. The network shared posts won’t work for me because it gives you a shortcode, and I need to add my own carousel script. Also network recent posts is not exactly what I’m looking for. I want to be able to tag any post across the network as “featured” (with a category or otherwise) and create a template that will display the first 5 or so in a carousel. Any ideas appreciated!