Hi Fenyi,
Thank you for your time!
I did you project. It works. But the Wio Terminal can only receive orders not give them.
-I have the bl adress from the bot.
-The serviceUUID.
-The charUUID.
-The writeValue.
This can not be that hard… 
I have used the Wio Terminal as RTL8720DN Dev Board and the BLEClientScan works and see the bots.
Maybe my problem is that I have been re-using sketchs made for the ESP32 instead of RTL8720DN (but both use #include “BLEDevice.h” (¿?).