Seems some people here advocate for a VPS, and I do it as well. I pay roughly 7€ a month for a small(ish) server with 4 cpu cores, 8GB of RAM and 256 GB of storage. That allows me to host a few services there, for example some websites and matrix chat, which I don’t want to go down if there’s an issue at home. And it allows me to do reverse proxying there, so I have the entire chain under my control. But there’s many ways to do it, and several other tunneling solutions (boringproxy.io, nohost.me, pagekite, ngrok, …) that I heard of.
And a lot of home internet connections allow port-forwarding. Not sure what your provider does, but I can simply open ports in my router and make them accessible from the outside, no VPS or Cloudflare needed. That’d be the direct solution. (And what I use for my personal services on my NAS.) Just mind that discloses your internet connection’s IP address to visitors, so they’ll learn the name of your provider and your rough location.
I’d rent one (small) VPS for $10 a month and split the bill. As far as I know that’s how most people do it. It’s going to have >99.6% uptime, a fast datacenter internet connection at some central location and runs on enterprise hardware… The Kubernetes approach adds a lot of complexity, you’ll have your games disconnect anyway once it fails over as you can’t migrate the IP addresses. And there will be some additional traffic between the locations to keep everything in sync. And 4x chance of some of the hardware failing and someone needs to fix it. Unless I’m mistaken about how Kubernetes works.