STM8 version of LCD2USB (AVR) is available on github

It is a modification of a working STM8 VUSB library from STM8S-VUSB-KEYBOARD.  The  Russian comments are "google translated" to English.

I have done some additional changes in the USB stack for the Vendor Request packets needed by LCD2USB.  I have changed the device library files to bare metal, refractor the code. etc.  I have taken the packet processing core from AVR LCD2USB, but used my own code for the I/O.

A general purpose schematic and PCB for Eagle is available.  The serial, I2C pins are broken out with spare footprints for a tiny crystal (available on aliexpress) and caps.

I am using 3.3V for the character LCD panel.  See ELM's article for details.  Contrast is controlled by PWM that drives the charge pump.

I am not sure if/how the buttons (S1 and S3) works with LCD Smarties.  LCD2USB.dll doesn't seem to an entry for them.

LCD2USB works with LCD Smarties LCD2USB.dll plugin as a info display.  It should work with lcdproc in Linux (not tested).