I have a reverse proxy set up already. The path from the outside goes:

DNS -> my IP -> reverse proxy -> server

I’m just wondering what happens when my own devices on the same network go to the domain.

The FLIRC Skip 1S might be your best option. The software for it is a little finicky but you can program the volume button up/down to fire multiple volume commands. One button press could control a bunch of different TV brand volumes.

I’m not sure if it can control the shield, but you may be able to program it.

The hard part about Jellyfin is that it requires your own domain and some more self-hosting knowledge that a hobbyist might not have yet.

It’s not a super hard transition, but it took me a few months on/off to learn the basics of hosting a website from my house.

I’m still trying to figure out headscale on a VPS so I can mask my home IP