Clean them and dry them then put them in a plastic bag and pop them in the freezer for a couple of days.
-22 Celsius kills the bacteria that cause the smell
Jesus, that’s a hell of a freezer you’ve got! Most only go to about minus two or three, I believe.
It won’t help if you’ve got athlete’s foot, get some Canestan thrush cream (the thrush version has 2% clotrimazole while the athlete’s foot version only has 1%) and sort out your feet, which will stop them smelling and infecting your shoes. Spray the insides of all your shoes with an anti-fungal spray like Scholl make. Dry cycling shoes after every ride with the insoles out, sunlight is good because the UV kills bacteria. Febreeze might mask the odour a little. You can also wash sports shoes in the washing machine.