They do indeed, but whether it's to do with Cloudflare screwing with federation, I'm doing something wrong (which is more than possible), or the communities straight up don't exist yet, I've found that you're better off going straight to a Lemmy instance to find a magazine than trying to find it via kbin itself, before this link of course.
I know you can do something like search for @gaming, but it would be nice if you could just search 'gaming' and see all other federated magazines. I believe you can only do said 'gaming' search and get results if someone else has already subscribed via that particular instance of kbin?