Hi Florian,
Good job.
I noticed yours uses the original wifi module with cloud integration.
It should be possible to use the original wifi module locally together with my solution.
However, it needs some work, as it currently cannot handle the initial response from the original Wifi module, which is “Hello”, but basically, it is just a serial2lan converter…
Too bad I sold mine after I had the info I needed 
And the esplink is defenitly a lot cheaper…just a few euro’s 