Hi all
So I created this housing for us:
see: Printables
With that, you can mount an OLED display, an WemosD1 (ESP dev board) and a random 4-pin sensor into one housing and power it through USB. That brings in my case the I/O extension from and to HA to live. I am able to send data via mqtt to the EspEasy instance and retrieve through an BMx280 temperature, humidity and pressure.
It displays as you can see in the pic the local and remote data for the 3 measurements.
The cutout is made for a 4-pin 2.54 raster.
You can also upload HomeESP, but in my case, the mqtt pub/sub is used across more systems than only HA.
Have fun printing and building!