Accept Date(AcceptDateTime) on Agent Work is populated when the agent accepts the Work Item(Case, Chat, Messaging Session, etc.) via Omni-Channel Widget. So, we can use this field to to find each agent accepted Salesforce Omni-Channel Work Items per day.

1. Create a Custom Report Type with Agent Work object/entity.

2. Create a Report using the Custom Report Type created in Step 1. Group the report using Accept Date and User: Full Name fields.

Using the above Report, we can easily find how many work items were accepted by the agents from Omni-Channel per day.