Don't commercially available software controlled USB hubs exist already? The Yepkit YKUSH 3 came to mind immediately (https://www.yepkit.com/product/300110/YKU

Don't commercially available software controlled USB hubs exist already? The Yepkit YKUSH 3 came to mind immediately (https://www.yepkit.com/product/300110/YKUSH3 https://www.yepkit.com/product/300110/YKUSH3) and is the only device I've seen that explicitly says that it disconnects both the data lines and power lines when switching. A casual search also finds https://www.usbgear.com/managed-hubs.html https://www.usbgear.com/managed-hubs.html