Hi Janine,
I came across some guidance that may help.
The available languages in the Summary configuration are populated based on the Agent Copilots already configured in the organization. If no Agent Copilot exists yet, the Language list may remain empty.
If you haven't created an Agent Copilot yet, you could try creating one first (using English (en-US) in your case) and then return to AI Studio > Summaries to see if the language becomes available.
I tested this in my org, and the Language dropdown is populated correctly (see screenshot below), but I already have an Agent Copilot configured.
If you've already created an Agent Copilot and the Language list is still empty, I'd recommend opening a Customer Care case for further investigation.
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Raphael Poliesi
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