The motherboard is overkill except it's not. You could shave $30 or $40 off the motherboard price, but then you would need to find/install a wifi card of some sort which is at least $20 for the cheapest one that isn't complete junk. In addition, this motherboard will serve as a great platform for upgrades as she gets older. The AM4 socket will be used for at least the next 2 years worth of Ryzen CPUs. So, when the new 2021 Ryzens come out and the 2020 Ryzens go on discount, you can inexpensively and easily upgrade her PC with one of the 2020 CPUs.
PCPartPicker part list / Price breakdown by merchant