How to get a complete model history per testing sample in each epoch instead of just one average value per epoch?

So let’s say I have 1 metric I want to monitor across the mode fitting process. So far, I’ve adapted the default CallBack function which allows me to get one single value for that given metric in each epoch. With this, I can save a time-series (just as with CSV logger) plot to check for the performance evolution but it doesn’t provide robustness results. Therefore, I would like to get the metric value for every sample in each epoch and save it, allowing me to get a time-series plot with a 95% confidence.

Thank you