Hey there,
So I found many different guides on running this or a similar setup on Hassbian, but none for Hassio so far (if this is even possible on Hassio).
Since I do not have NAT-Loopback, just using DuckDNS+Let’sEncrypt makes some of my services not work properly (e.g. REST or TTS from inside my network). Switching to NGINX would still allow me to have a secure connection from the outside to my pi, but use non encrypted communication within my network.
But I need help setting this up.
There is also another NGINX proxy variation here that uses certbot to obtain Let’s encrypt certificates, and I tried to set it up, but failed (now I reached the limit for certs on Let’s encrypt for this week 
)
Help is muchly appreciated.