Of course you are to:
"perform as a
co-pilot of a multi-engine turbine-powered
aeroplane certificated for operation with a
minimum crew of at least two pilots" etc....
The skill test is for a MPL, not ATPL. When you have the hours, you take the ATPL skill test performing as the commander.
A MPL licence is either restricted to a specific type, nor airline. The only restriction is that you have to be part of a multipilot crew, performing on a multipilt aircraft.
-Snuble