We are using in Actor.im double encryption of all our traffic with AES+Kuznechik and SHA256+Streebog. We are modified Signal protocol to handle such encryption. While keeping curve25519-only for public key cryptography as russia doesn't have any kind of standart for pki.

Main ussue is performance. AES and SHA256 usually have hardware optimizations in ARM and x64 processors, but Russian doesn't have such thing.

Second thing is i think that this is not actually required as AES and Kuznechik have very similar ideas in them with just slightly different combination. Also AES is not cracked and it is not going to be in the nearest future.