There's no such thing. The closest thing to that would be to volley a person. The person who doesn't keep the ally makes some gold off that. There's no way to just transfer gold though.
Actually volleying is called as gold "transfer" but there are another way how to "transfer" money. 1st - Make an alt, or use your buddy to "transfer" money by volleying. I suppose u know how to do it. 2nd - open it/yourself as OSF and hit by droping pots, this way u probably can "transfer" a lot, only thing u need to hit a lot.
So basically there no real way to transfer big ammount of money just by volley a player or open osf and it's a small amount though. Thanks for the help
For me the most efficient way is to buy an ally at 141 mil and volley him to 30 bil then drop. If you do this you will transfer 4 bil while losing about 6. If you go over 30 bil then you are losing too much money for my tastes, but some do such high-level volleying.
This method was actually extremely efficient, but devs pulled it out a while ago. It used to be what... 90% efficient? Now it's about 60%.