These let you do the same thing as powerline, but with the Coaxial cable TV ports in your walls instead.
If you really want to get fancy, pull out your old phone jacks and follow them through with CAT6 ( and new phone wire if you want to keep both). You don’t need to wire everything; buy some WiFi APs and keep the router in the basement, and run hardlines to your APs (an AP or Access Point is just the WiFi part of what you think of as the router, it doesn’t do any routing, it just goes from wired->wireless)