Now that KyPass have full webdav support, you could synchronize with box.com and mydrive.ch.

For box.com,
You have to enter https://<your email>:<your password>@dav.box.com/dav (be sure to replace the @ by %40 in your email)

For mydrive.ch,
You have to enter  https://<your login>:<your password>@webdav.mydrive.ch

You have another webdav configuration for known cloud provider? Don’t hesitate to add it in the comments.