BRO TRIP 40,000: A Tale of Two Primarchs is a spin-off series to If The Emperor Had a Text-To-Speech Device, staring Vulkan and Corvus Corax as they make their way to Holy Terra. Along the way, they stop at various planets where they get introduced to various local cultures and famed Imperial Guard regiments. The series was introduced in Episode 25: Fiery Family Reunion.
The show has its own Spin-off called WarHams, a Tabletop RPG game series set within the BRO TRIP crusade.