You'll need to do those "manually". For quests, you need to be in a party. Form one from the players list (default key 'i' I think, click on plus)
Find the quest you want to share in the quest log, on the top you'll have an icon for sharing, looks like a group. Once you press that, the other people will have to accept it, opening the quest log and looking at the bottom, there's a short list of shared quests, pick one and click on the tick icon right above.
The same process goes for map markers, but you'll have to pick to share between allies or every one. Everyone will have to accept them as well.
