Apologies if there is already something like this, this is just something I thought of the other day. Thought I would post it before I forgot it.
Basically the Sync gate is like a normal gate but the user chooses one of two options among other oprions. They choose either to make the gate a primary (master) or a secondary. IF secondary is chose, there is a small window on the gate that asks for what channel. The user clicks in the window and drags up and down with left click or types in the channel. Now the gate is in sync with a primary gate. Whenever actions now happen to a primary gate, all the secondary gates also do the same. And I guess you could make it even more complex by having a primary gate channel along with secondary gate channel.
Oh well, just thought it was something that might come in handy.