As a multi-core project, set information on the individual application projects related to the boot loader project in the boot loader project.
Afterwards, the application projects are automatically built and associations with the addresses of the symbols this produces are set up whenever you debug the boot loader project, which eases debugging. The hex files generated from the individual projects are also combined in a single file.
See “2.10.1 Set the constituent application projects” for details about setting up the associations. See “2.10.2 Combine multiple objects” for details about producing a combined hex file.