Android OS - strange UDP traffic on port 123
There is a simple answer what is causing the UDP traffic.

The first indicator is the used port number 123 which is typically used by the Network Time Protocol (NTP). This protocol is responsible for synchronizing the time of your smartphone with a remote server.

To spread the burden among multiple servers and to make sure there is always a server available the NTP protocol usually does not use one specific time server to synchronize with.

Instead a large pool of servers is used. The three IP address 118.189.138.5 95.216.192.15 133.243.238.163 and 202.12.97.45 you mentioned are all NTP servers and they belong to the NTP pool "Asia 1". 

Therefore if you capture more traffic earlier or later I assume you will see all of those IP addresses with UDP traffic on port 123.