Probably not, you would have to do a lot of manual checking. This is why the
RFY program exists.
It would seem that Freedombox would at minimum have the same issues Debian
has since it is based on Debian. Moreover, because this supports several
SoC's I don't see how that can work with a de-blobbed kernel because various
proprietary bits are needed for the various boards the project supports.
As I am sure you are aware based on the specifics in your questions SoC
boards are really problematic, there is a good reason why none are officially
endorsed and their architecture isn't supported by libre o/s's
https://www.fsf.org/resources/hw/single-board-computers
