The Problem: Migration Traffic to Expatriates
Adding a migration target to Expatiates isn't currently an available option since SE doesn't add migration paths to sites in beta:
In addition, most of the traffic on Expatiates comes from migrated questions, which in itself could be an indicator of an unhealthy beta.
The Solution: Guiding Users To Expatiates
One possible solution to this problem could be adding a brief sentence on our ask page pointing askers to Expats. Our ask page currently looks like this:
If your question is about immigration or moving for extended periods of time, ask it on Expatriates instead.
Feel free to post your own ideas as answers.