How can I add PO items and its details into PO email template to approvers for approval in S/4HC?
I found this from the community and this may be helpful to you,
The best practice that applies is 1LQ (Output Management)
There is a good guide there that gives a lot of examples:
Here is the help for customizing emails:
For your particular question, you don't mention which email you want to customize, but need to determine if the field exists in the datasource for that email output.
It may be possible to define a custom field to include (you might be able to populate the custom field via a BADI). if you can provide more details, we can help.