I've read some about how they will work.

You need to be at a shrine and complete the ritual with the one you want to share with.

IT has been stated that you have to be in party. But do you have to be close to each other? Or just in the same party, and on the other side of the world?
I personally think that just beeing in a party should be fine, not having to be close.

I mean, I have a few friends playing the game, but we can't share all of us, since we play in diffrent time zones, And we might end up beeing an odd number. It's just my hopes I guess, since it would be more fair that way.