See my comment below. Since Meta Stack Exchange was separated from Meta Stack Overflow in 2014, it no longer never makes sense to expand [metaso] to Meta Stack Exchange.
Also there's currently no magic link for MSO ([mso], [meta.so], [so.meta] do not exist), so it'd be convenient and reasonable to redirect [metaso] to MSO, and alternatively make [mso] work. Adding magic link for Meta Stack Overflow?
[MetaSO]is expanding to Meta Stack Exchange. And [mso] [meta.so] [so.meta] do not exist.[metaso]and[meta.so]should expand to Meta Stack Overflow and[meta.su]should expand to Meta Super User.