Hong Kong: https://www.immd.gov.hk/eng/services/visas/pre-arrival_registration_for_indian_nationals.html says
Pre-arrival registration is not required for Indian nationals in direct transit by air and not leaving the airport transit area.
China: https://www.travelchinaguide.com/embassy/visa/transit.htm says
For foreigners who hold tickets to a third country and have booked seats on international airlines, ships, trains transiting through China, if the stay is less than 24 hours, they can enjoy the 24-hour visa-free transit. In case they want to leave the specified transit zone, they can ask for a temporary stay permit at the immigration counter. The 24-hour direct transit facility benefits almost all country citizens and is available in most China ports
Malaysia: http://www.kln.gov.my/web/ind_chennai/faqs says
PASSENGER WHO INTENDED NOT TO LEAVE THE AIRPORT
If you are already check in for the next flight and do not plan to leave the airport terminal (i.e. you just want to wait for the next flight in the terminal building), Malaysian visa is not required.
I don't know where MY is, so I can't tell if you need a transit visa or not.
Note: All of those were found by typing
<country> transit visa in google. Why didn't you do that?