Do you have to be ME to do MCC?
There is no explicit MCC course pre-entry requirement in JAR-FCL 1 for a MEIR or, indeed, a valid IR of any kind or even an MEP class rating. The UK CAA have, apparently on the basis of the statement that the course
"is intended to provide MCC training....for PPL/IR or CPL/IR holders....", decided that a valid IR is a pre-requisite, although I'm not sure where that is published - it's cetainly not in LASORS. I would not be surprised if, by extension, they were to take the statement that
"Wherever possible the MCC training should be combined with the initial type rating training for a multi-pilot aeroplane" to imply a requirement for a valid MEIR.
There are no pre-requisites whatever for entry to the MCC course in EASA Part-FCL, either explicit or implied. Of course this does not prevent a course provider introducing his own pre-requisites to filter out those he believes would not cope with the course.