USB 3.0 internal splitter for internal ports
USB 3.0 internal splitter for internal ports
Splitters are available. They're problematic. Using all ports and devices simultaneously undermines their usefulness if they work at all. You'll have to choose one of the following: A - Set up a workaround to route USB3 ports through the back of the motherboard (a method that was once popular but is now uncommon, requiring drilling or similar fixes); B - Use an adapter to connect USB3 ports to a USB2 header (this slows them down to USB2 speed, though it might still work depending on what you plug in); C - Switch to a different motherboard.
Consider using a PCIe card to increase the number of USB3 connectors. https://www.amazon.ca/PCI-Ports-Header-E...B07Q294CXG