This is not specific to the PI.

Use this command:

 iptables -t nat -A PREROUTING -p tcp -d 192.168.2.93 --dport 19132 -j DNAT --to 192.168.1.101:19132

Replace `tcp` with `udp` if you need UDP.

The options `-d` and `--dport` specify the original destination host and port. `DNAT` means destination NAT, you want a different destination. `--to` sprcifies that destination. Table `nat` and chain `PREROUTING` is the place to do this.