For each of the directories, generate a digest file:
find DIR -type f -exec shasum {} + | LC_ALL=C sort -d -k 2 > shasums.txt
It's important to use LC_ALL=C and the option -d of sort, to get compareable results on different machines.
After that, you can diff the two shasums.txt:
diff shasums1.txt shasums2.txt
Or you use Meld as graphical diff tool:
meld shasums1.txt shasums2.txt
cli sysadmin