For cloned tickets (originating from SMR), can updates be sync'ed bi-directionally?
If a cloned Jira issues is updated, can that update be pushed back to Service Management Request?
Similarly, with Jack's answer, it is possible, but you'll need some automation to do the work for you. You have the built-in Jira Automation for Jira Cloud, while for server/data centre, you might need to purchase one, maybe Scriptrunner.
We have a similar implementation with tickets assigned to a service team. We created a link between the cloned ticket and the original ticket; that will be the reference you can use to perform the uni/bi-directional sync.
With a bit of work yes/likely. However this isn't going to happen by the fault just because an issue as a clone. What you would need to do is to link these issues or create a custom field that could be referenced within an automation rule. You could use automation to update the cloned issue based on that link or field. If this doesn't make sense let me know.