A simple change I’ve made for most every athlete I work with is to elevate their heels when squatting, which gives us more ankle mobility along with an anterior weight shift that helps counter balance during squatting. I think, almost without fail, people end up squatting in a better position and their ankle mobility (or lack thereof) isn’t a limiting factor/reason for not-so-great movement quality.
And yes, we do work on ankle mobility. But when you are working with really tall athletes (volleyball and basketball) that don’t have levers in their favor, the added help can go a long way ➖and when you are working with hockey athletes who live in a skate (essentially a cast) you are fighting a constant uphill battle to keep ankles mobile.