Since I have 2 servers is there any Plugin that allows a person to join the other server by just pressing or clicking a sign???
If you are trying to transfer a player to another server with a sign, you only need TapToDo. The /transferserver command is already in pocketMine. https://poggit.pmmp.io/ci/Falkirks/TapToDo/~
I bet we really need a plugin that fires preprocesses signs and fires an event to retrieve such variables...
Adding to what has already been said, you could use SimpleWarp and WarpSigns. If you are already using SimpleWarp for other warps, this would be a good way to go.