Mount Cryptomator directly in your Synology NAS. The files will be accessible via WebDav protocol.
Docker Hub: https://hub.docker.com/r/vh13294/cryptomator-synology
In Synology NAS
Volume
Port Setting
Environment
In your WebDav client (guest account, no username/password)
(Assuming 192.168.20.200 is your NAS IP)
You can also mount WebDav as remote connect in synology file station.
[File Station] -> [Tools] -> [Remote Connection] -> [Connection Setup] -> [WebDav]
Hostname will be 'localhost' or '127.0.0.1'