Trying to migrate this question to another SE site
Migration, though, only lists meta as the only option.
Is this a bug? or What?
For what it's worth, I tried looking at the "flag as off-topic" process on another site I'm on (German Language), by clicking on "flag" for a question I wrote (without actually submitting the flag itself). There, the only migration option open is the Meta for that.
The same goes even for a third side (anime and manga) where I distinctly remember a question once having been migrated from there to the Mathematics.SE.
So I'm given the impression that via the normal closure / off-topic flagging mechanisms, the Meta for the same site is often the only option. Not sure how questions get migrated then to different Stack Exchange sites. (Moderator attention, perhaps?)
Update: For what it's worth, I also looked at the "should be migrated to another site" options on Mathmatics.SE. There, I have the options of the meta site, the statistics SE, and the physics SE. This seems to indicate that the migration options are preset.