I suffer from ankle sprains alot. I have sprained the same one BAD 2 years in a row. First sprain was Grade 2/3, the second was 2. I was literally still feeling pain 6 months after the event.
Here is what I did and I'm sure you can find tons of methods...
I first addressed calf function/strength...
tibialis and peroneal function/strength...
Glute medius isolation...
then integration into squats/deadlifts/good mornings
SIngle leg work: lunge, Bulgarian splits
Power: lots of jump rope
Tons of SMR in the calf and top side of foot. If you really strengthen the muscles of the lower leg, you'd be surprised at the "reaction" time you develop when you "feel" like you are rolling your ankle. Nervous system stays on "heightened alert"...
good luck