How to create watermark with exif data

[storageman]

I have been told that XnView can be used to create a watermark containing text like "Vacation 2015" but I wish to extract the timestamp from the exif data and add to watermark.
This MUST be a common use, but I have wasted the last 2 hours attempting as well as searching this forum.
Help
(Even Google did not help)

[cday]

I have been told that XnView 'Classic' can be used to create a watermark containing text like "Vacation 2015" but I wish to extract the timestamp from the exif data and add to watermark.

As far as I can see that is currently only possible as a two-step process: XnView Image > Add text... can be configured to write text plus selected exif data to an image, and then Image > Add Watermark... can be used to apply the image with added text as a watermark.

But I don't see any way to implement that as a batch process, as currently neither XnView 'Classic' nor XnViewMP (nor XnConvert) support writting exif data as text in batch mode, and the text would in any case (I presume...) be appled to the source watermark image rather than to a copy, which would be an issue if the exif data changes from image to image...

Possibly someone knows better??

Edit:

Possibly you are asking about adding 'text plus exif' data directly to an image, which is possible using XnView 'Classic' XnView Image > Add text... although not in batch mode, rather than adding the text to an image which is then used as a watermark?