A way to see how much time an export of images takes? In lightroom is there anything that will show how much time it has taken to export images? or even a text files somewhere that shows the start and end time of the export of images?
You have the progress bar (top-left) in the Library.
You'll need to use a Stop Watch and watch the Progress Bar. Upper left hand corner of the LR window.
Look at the timestamps of the files (not the shoot time, the modify time stamp). If you export a bunch of files, say 100, you look at the first and last and divide the difference by 99. You get the exact average time it needed to export one image.
This however does not mean that the next 100 images will take the same time. Only when size and edits are similar, times will be similar.