Overlapping with other sites is a perfectly normal thing. In fact, they are healthy for sites. Don't be concerned that just because one thing is on-topic on one site, doesn't mean that it will have to be off-topic here.
However, let me raise one thing: beta sites cannot migrate questions. Don't make the assumptions that you can do this, because you can not. If something is off-topic, please use a custom off-topic reason, so that the entire community can thoroughly understand why.
You'll have overlap. I'm a pro tem moderator over at Open Source. Will you have overlap? Of course you will. That's perfectly fine, you have nothing to worry about.
Focus on this site, not others.
This post has been migrated from the Open Science private beta at StackExchange (A51.SE)