Can dermal fillers be used in the ankle to give it shape so that it will look like a standard ankle?

Filler is not FDA approved for the ankle area.  You may be hard pressed to find a provider to perform this for you.  They also don't last forever and you would need to repeat the filler at least every 1-2 years.  You'd be better off saving your money and doing the surgical procedure.  In the end, it will be cheaper and safer.

To correct changes like this, you will require a lot of filler, explore fat transplant, or surgical options. NHS does have a 'compassionate' list if this applies to you, depending on funding of your catchment area. All the best, Dr Davin Lim. Brisbane. Australia.