Question: have Toyota Denso 175800-9631 ECU, how to read/write? Can ECUHELP KT200 works? I attach the ECU image below:

ECUHELP KT200 : No
ECUHELP KT200 is not able to read/write Toyota Denso 175800-9631 ECU, please refer to the KT200 Toyota Denso Support List:

PCMflash 1.2.0: yes
Hardware: PCM Tool Super J2534 67 in 1 ECU Programmer
Software: PCMflash 1.2.0
ecuhelpshop.com engineer recommends PCMflash 1.2.0 to virtual read / write Toyota Denso 175800-9631 ECU.

Others:
KTAG can work with the BDM frame. KTAG is a master tool that can read and write various ECUs via JTAG. However, you might also need to find the programming pads on your ECU board. Alternatively, you might be able to do OBD (On-Board Diagnostics) with the correct tool, such as genuine Kess or X17. These tools can perform virtual read and write operations on some Denso ECUs.