What it would be
A card at the standard European size, 85 by 55 millimetres, printed on both sides. The front is the shop: name, the person, how to reach them, where they are. That side has nothing to do with Worldwatch and should not.
The back carries the verified mark and the member handle, with a code that resolves to the dealer's verified profile. A card that someone can check after the conversation is a different object from a card that only asserts something.
What has to be settled first
Which mark is approved for print use and at what minimum size, what the verified profile URL is, and whether Worldwatch supplies a file or a finished print run. Those are three separate decisions and only the first is a design question.
Until then, the kit overview lists the rest of what is proposed, and contact reaches the people deciding it.