Step 1: Record your chat list

1. Swipe down twice from the top of the screen. Tap Screen recorder, choose No sound, tap Start.
2. Open WhatsApp Business on All chats. Scroll slowly and steadily from the top. Do not fling the list.
3. Stop the recording with the red button. Record 5 to 10 minutes at a time.

Or take screenshots, including Samsung's long scroll screenshot. This app reads those too.

Step 2: Choose your recording

Step 3: Read the numbers