It’s being a wile.
I recently had inspiration to make my JL1 wireless, with self imposed constrain to use no additional hardware, only original board. It had that functionality originally!
Today I’ve succeeded: JL1 firmware recompiled to talk on second UART of STM that is connected to ESP12F.
There is large selection of projects to used ESP as WiFi-to-serial bridge. I use ESP-LINK for that.
All comes together nicely, IMHO.
See LsrSal JL1 Firmware on GitHub for details and firmware files.
I consider it Alpha, little testing, but so far all appeared to work as intended.
It is kind of satisfying to have one less wire but no loss of function. 