In general any kind of location-dependent moving can be achieved by defining several versions of the piece, and morphing those into the version that is needed on their destination. So in this case you would need separate types for the 2nd rank and elsewhere. (Which also means you can do it entirely transparently, giving the types the same image and ID, as the morph parameter will never make a specified type morph into itself, and will thus always pick the other type with that ID. If that still leaves choice it will pick the type that occurs last in the piece table.)
There could be an alternatie here: for the benefit of Crazyhouse I once defined ii to mean 'repeated initial move', i.e. a move available when the piece is in its initial location. This is defined as any location on which a piece of that type started. So if the 2nd rank is initiall entirely filled with pieces of that type, the ii move would be reactivated each time the piece returns to 2nd rank.
In general any kind of location-dependent moving can be achieved by defining several versions of the piece, and morphing those into the version that is needed on their destination. So in this case you would need separate types for the 2nd rank and elsewhere. (Which also means you can do it entirely transparently, giving the types the same image and ID, as the morph parameter will never make a specified type morph into itself, and will thus always pick the other type with that ID. If that still leaves choice it will pick the type that occurs last in the piece table.)
There could be an alternatie here: for the benefit of Crazyhouse I once defined ii to mean 'repeated initial move', i.e. a move available when the piece is in its initial location. This is defined as any location on which a piece of that type started. So if the 2nd rank is initiall entirely filled with pieces of that type, the ii move would be reactivated each time the piece returns to 2nd rank.