The author of rclone answered a question about this kind of thing here. Here's his answer copied below.
rclone doesn’t have a bisync solution at the moment.
There are some ideas on implementing it
And even a 3rd party tool or two
You could do:
rclone mount YourRemote: /mnt/remote1
and then use:
rsync [flags] /mnt/remote1 /your/local/directory
rsync [flags] /your/local/directory /mnt/remote1
or something like unison.
With the right flags rsync both ways might do it.
See this question.