This is Homeassistant, MQTT broker - Mosquitto, Node-RED installation. Requires Android 5.0 and up. Works without root. Install Termux and Termux:API from play store or F-droid. Install Hacker’s keyboard. This works for me, why you have a problem with this i don’t have a clue. :)
If you started homeassistant with hass after you installed it with pip install homeassistant. There should be a .homeassistant folder. ls -A to see hidden folders.
Run termux-setup-storage. Then you can copy configuration.yaml from termux with cp /data/data/com.termux/files/home/.homeassistant/configuration.yaml /data/data/com.termux/files/home/storage/shared. Now it shows on my phone in /storage/emulated/0. When you finish with editing just copy it back to .homeassistant folder.
There is no username and password in default mosquitto config. It allows anonymous connections. You can set password with mosquitto_passwd. Google is your friend.
Is it just me or is mosquitto having a wrong timestamp (-2 hours for me, Europe/Berlin) ? Maybe because of a missing timezone file? Any idea how to fix this?