Ledsteplin
Ambassador
It's one gmail account, not two. That one single gmail account is added to both devices. It works, I've done it/am doing it.
You're right, you can't. That's not what I am suggesting.
This is just an example; create a new gmail account shared4us2@gmail.com and import a copy of your contacts to that account. Add shared4us2@gmail.com to your iPhone and set it to only sync contact info (as in the screenshot I posted above). Then install shared4us2@gmail.com on your wife's iPhone and set it the same way, contacts only. There's no emails being sent through shared4us2@gmail.com, but the contacts are synced regardless of how many devices you add that one specific account to.
You can add shared4us2@gmail.com to as many devices as you want of any type that supports gmail, and every single device will have the same contact list for that specific gmail account. I do this all the time. An iPhone can have several gmail accounts added.
So how do contacts get in the Gmail account?