I have powerful router Turris Omnia and I’m running Apache on it. Unfortunately, it’s running on OpenWrt, which is not supported by certbot-auto. Did anyone try to use certbot to get certificates for Apache on OpenWrt? I’m primarily a web developer and things like cross-compiling are Greek to me.
My website https://wiki.findrbot.com/compile-package-openwrt shows you how to do lots of things, one of them being compiling a package for OpenWRT. You can use that tutorial and see if you can compile newer versions of the packages to get the dependancies you need to install letsencrypt binaries on the router.
I have an OpenWRT router, I will see if it is even possible, and reply back if you haven’t sorted it out.