In separate pots, possibly - but it depends on the size of pot (the Willow will need a large one, and potting on every year into an enormous one eventually) and on the size of the shrub you're thinking of planting. Smaller shrubs like Skimmias will do well in the right size pots - large ones like, say, Cotinus, will do much better in the ground.

If you go into your local park that has a lake or pond you are most likely to find a salix (willow) growing next to it with its roots actually in the water. Likewise if you wanted to grow a salix in a pot, it would be difficult to supply it with enough water. As suggested, put it in the ground.

you can ofcourse bonzie the willow .

I was assuming the 'willow' would be Kilmarnock or S. Hakuro Nishiki, the most commonly planted willows - its unlikely to be one of the large ones.