Hi @jeremias.tx,
Since your colleague @bruno.tx was able to give us a suitable alternative for data encryption (Write recipe for gocryptfs - #3 by bruno.tx), there is currently no urgency for fscrypt to work with ostree.
However, since fscrypt is a much more convenient and secure solution than GnuPG or OpenSSL, it would definitely be an interesting feature.
Best regards,
Markus