You can export the sequences generated in Design by downloading the structures’ PDBs or FASTAs. Begin by opening the file containing your Design results.
As shown below you will be able to select the structures you would like to download data for by checking the box next to each structure’s name. If you would like to download data for all the structures in the collection select the top most box.
Once your structures have been selected click 
, located at the top right. As shown below this will open a drop down menu where you can choose to download either the PDB files or FASTA sequences for these structures.
Additional information on how to analyze the FASTAs from Design results can be found here.