Please note that the command Enable-RemoteMailbox is available only in on-premises Exchange, so we should run the command and create the role on-prem as well.
We can use Get-ManagementRole -Cmdlet xxx-xxx to check what roles are need for running the command. So here for Enable-RemoteMailbox, it requires below roles:
Then you could create a new role group contain the roles above for the team you specify:
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