Planka looks like a really good option! I don't suppose you know if the timer feature has some sort of report available - being able to export the time spent on each card?

Whoogle is what I’ve been using for a couple years. I found that you ideally need multiple IPs to query from though as it can quickly get rate limited by Google - if you perform a few searches in relative quick succession.

Do you know of any other’s like the murder mystery one?

The murder mystery is great! I modded it slightly to track the queries run, it helped me understand how my team were progressing with learning the language.

One of that team actually copied all the tables to Excel and proceeded to work out the answers there … they get the right answers to be fair!