I'm going to second preschoolians.
You want a shoe that's very flexible and doesn't have any "arch supports", but lets the developing foot move like when bare. A high instep plus too much arch support and rigidity leads to atrophied tendons and ligaments in the foot, then fallen arches. The human foot is pretty well adapted to walking, if allowed to develop unimpeded. Our cultural tendency to interfere is probably to our own detriment. Feet need to be protected from hazards, not imprisoned.
Preschoolians come with 3 sets of insoles, so you can put in the wide ones to adjust to your child's wide foot. Several of the styles have velcro closure and no tongue.
breastfeeding, babywearing, homeschooling Heathen parent to my little Wanderer, 7 1/2 , and baby Elf-stone, 3/11!