if i am taxing ultron with U shadowcat on a indoor map, can i proceed to drop off ultron on the other side of a wall then on my next move pick him through the wall and leave.

With a wall seperating them they are not adjacent.

Jackalope is right. You cannot drop Ultron off on the other side of the wall because at the end of the carry, you need to drop the figure off in an adjacent sqare. You cannot pick him up if he is on the other side of the wall for the same reasons.