Setting up work from home agents with Twilio Flex can be achieved by changing the default codec to Opus, which delivers higher voice quality while using less bandwidth, and utilizing the Twilio Voice Client for routing calls. A company in the US was able to keep their existing telecom infrastructure intact while implementing a solution that allowed their 800 contact center agents to work from home using Twilio Flex and the Twilio Voice Client, with modifications made to the client-voice function to route calls to the correct destination. The changes can be made through the Flex Configuration API or by modifying existing functions, and it is recommended to use a secure solution in a production environment.