Git supports showing diffs for encrypted files, but has to be told to do so.
git config --global diff.gpg.textconv "gpg --no-tty --decrypt"
echo "*.gpg filter=gpg diff=gpg" >> .gitattributes
echo "*.asc filter=gpg diff=gpg" >> .gitattributes
or
curl -sL https://gist.github.com/marcelosousaalmeida/e6593b93b388cdf1dbc282dffd424d1b/raw/.gitattributes -o .gitattributes
pass
usestextconf = gpg2 -d --quiet --yes --compress-algo=none --no-encrypt-to --batch --use-agent
when configured as git repo