Just before Darren posted I was going to say scripting as well could probably do it. I've not really tested this, but if I were you I would script these steps. 1. Find the Shared Variable node. 2. Find the terminal of the node, read its coordinates. 3. Find the wire connected to the terminal. 4. Delete the node. 5. Place the new node at the coordinates of the old one. 6. Find the terminal on the new node were the connection goes. 7. Actually make the connection.
All of this via scripting nodes. Also as a side note, you may want to consider what you are replacing this with. Are you planning to replace all SV nodes with locals cause that won't work like this so easy. Are you replacing them with something like a message enqueuer or tag engine, because you may need to place a string constant to name the message or signal along with the replacement VI as well.
If you really want to do this, it can probably be done by scripting, though I haven't tested this I've done similar things. I would do the following:
1. Find the node to replace and read it's coordinates. 2. Find the nodes connecting wire. 3. Delete the Shared Variable node. 4. Place the node you want as the replacement at the same coordinates. 5. Connect the wire from the now missing SV node.
You may also want to consider that this won't work if you're drop in replacement is a local variable. I'm guessing you're replacement is a tag or message engine enqueuer in which case you may also be needing to drop string constants to indicate the name of the signal or message your are sending.