I’ve used Erugo a few times and been happy with it. Not sure if it does everything you need but worth checking out.

Thanks for the heads up!

Honestly Cloudflare Tunnels could be a very simple way to do it. I’ve always had tremendous luck with it. By using CF you can let them do all the heavy lifting instead of hosting your own… as long as you trust them.

I use Yomu across my devices and it works great. I’ll use highlighting for when switching between phone and ipad especially in between chapters. The formatting difference keeps me where I left off with the highlighting. It is $8 one time purchase.