I think if they went head to head as adults, they would probably be evenly matched. I would expect the hawk to win, but not without coming out of the fight injured. So it's an avoid at all cost scenario.
If you have a sparrow hawk turn up, as I did one time in my garden, every other bird will fook off out of sight, I've seen the damage they do to other birds and the panic they cause to nests. But a crow/jackdaw don't take no shhite either, so it would be an interesting battle.
