Irfanview is free and will imprint the date in bulk. If you want the current or last modified date you can just put $T in the box. If you want the EXIF date you have to put $E36867(%d%m%Y). You have to set it up only once and you can always print the EXIF date simply by choosing all of the images in a folder in the batch dialog or by holding the Ctrl key while selecting just the images you want to imprint from Irfanview thumbnails. I prefer doing everything from the thumbnails with "Select all" if I want them all.
In the batch dialog select the advanced options and check "Overlay text". Go to the settings and put $E36867(%d%m%Y) in the text box. Select a font and color. Choose the position you want it on the print. I prefer transparent but you can have the date in a box. Make the space large enough for your date. As I said you have to do this only once and from then on it will put the date on your prints.
You probably want to download and install the free Irfanview plug-ins to be able to read the EXIF. They install easily after you install the program. I would suggest selecting "Images only" for the associations when installing the program. www.irfanview.com
I would do a bulk rename at the same time or send them to a different folder to keep from ruining your originals.