Can I use three USB3.0 on TX1?

I will use R28.

Can I use three usb3.0 on tx1 as config #5
One on USB_SS0 one on USB_SS1 one on SATA.

And second question, can I use USB_SS0 USB_SS1 and PEX_RFU as usb3.0 pin same as TX2?

Hi, please refer to USB 3.0, PCIe & SATA Lane Mapping in OEM DG to choose which option suffices your need.