This video shows you a simple but effective and fast way to flash these old E-Paper Price Tags with a custom firmware.
Custom Firmware by Dmitry:
http://dmitry.gr/?r=05.Projects&proj=29.%20eInk%20Price%20Tags
CC2531 USB Stick Zigbee Access Point:
https://github.com/danielkucera/epaper-station
ESP32 Flashing Source by me:
https://github.com/atc1441/ZBS_Flasher
3D Printing Design:
https://www.tinkercad.com/things/37yG0A1sEFw?sharecode=woPw-7fiiAaOwkRt-xzJYHstxwA_3Xcl5dmdgnPgwAw
Pogo Pins:
1.3mm * 16,5mm
https://www.ebay.de/itm/373599814019
The ESP32 Board is an ESP32 Lolin32 Lite