When a player is trying to score in Association Football (Soccer in American English) and kicks the ball with too much power and with misdirection, so that it completely misses the goal (typically by going too high), is there an idiomatic word in British English to express that?
To sky the ball:
when the player has hit the ball too hard and it has gone over the bar - not just over the bar but a long way over the bar.
Although there are adjectives like “skyer” and simple phrases like “well wide” or “well over the bar”, a British football description more on the lines of what is requested is:
That one landed in row Z
The seating rows are numbered from A, at the bottom, so row Z is much too high.
or, if the ball wasn’t so high, a commentator would often say:
The ball was always rising
As regards the supplementary question/comment for an expression that is not specific to being too high or too wide:
The shot was well off target
is used, although not particularly idiomatic. A more colourful expression, would be:
That one scared the pigeons
although at Brighton, Blackpool or Bournmouth, it would be transformed to something like:
That one scattered the seagulls