1) Login to the account with the money you want to transfer, randomly trade someone and offer alot of coins then press accept. Now in the chat box it should say " you can only give away X amount of coins at the moment".
2) Once you have found out your trade limit go to a discrete location not very far from loadstones or teleports.
3) Drop the value of coins your trade limit allows. For example if my x value in step 1 was 11,034 then I would withdraw 11,034 coins from my money pouch and drop it in the discrete location.
4) Drop the remainder of the money in your money pouch ON TOP of the X pile of coins from step 3.
5) Switch to the account you would like to transfer the money to and rune to the discrete location and pick up the coins after they appear in about a minute or so.
*Note: When you click on the stack of coins both the X and the remainder are collected at the same time.