Assuming the agent self enrolled in direct deposit then at the bottom of each payment there is a link to adjust the destination, see below image.  They may need to setup an account in checkbook and may have to verify the new designation like they did the original.  

If the brokerage setup the account info in advance then you need to change that via broker.EZ.  

 https://faq.checkbook.io/en/articles/3517874-i-received-a-digital-check-but-don-t-have-a-checkbook-account 

https://faq.checkbook.io/en/articles/2712108-how-to-update-my-bank-account-information