Why can't I choose a specific BSP in MPLAB® Harmony Configurator ?
Why can't I choose a specific MPLAB® Harmony Board Support Package (BSP) using the MPLAB® Harmony Configurator (MHC)?
You can select a specific BSP, as long as the device you associated with the project is used on the development board you want to use.
When creating a new MPLAB Harmony project (or later on in the project properties), the appropriate device needs to be selected, otherwise, the corresponding BSPs for that device will not appear in the MHC interface.