Currently, when attempting to group tickets in the agent portal, it is not possible to group these by status, nor sub-status. It appears as though you can group them by almost everything else, including department, categories, priority, agent, agent team, and even waiting time or custom fields, but not by status. It would be good if you could add the ability to group by status and/or sub-status, to give a birds-eye view of tickets.
I realise that I can add filters for these, and group them that way, but it becomes unwieldy when you want just a quick grouping such as you can with the other fields.