What is USB-C:
A USB-C connector can transmit both USB and DisplayPort signals if it supports DisplayPort Alternate Mode.
Reasons to use a USB-C with DisplayPort Alternate Mode device:
You have a display such as the ASUS MB169C+ that only has a USB-C input.
You have a USB-C display adapter that you would prefer to use over a DisplayPort display adapter.
You have a USB-C hub that also has a DisplayPort output.
Problems to solve:
You have a computer (old or new) with no USB-C Alternate Mode ports, or not enough Alternate Mode ports.
You have a new computer with a USB-C Alternate Mode port (or Thunderbolt 3 port) but it is connected to the integrated graphics of the CPU and you would prefer to use the capabilities of a graphics card.
An adapter with one output: USB-C female connector supporting USB 3.1 gen 2 (10 Gb/sec), DisplayPort 1.3 Alternate Mode, and Power Delivery 2.0. The connector has to be female to support hubs and display adapters that use a male connector that cannot be detached.
The adapter would have 3 inputs:
USB input (3.1 gen 2; 10 Gb/s) from 10 inch USB-A male. The following would also work: USB-B female, or USB-C female with separate cable. USB-C male connector would not be acceptable as it cannot be connected to a USB-A female port.
DisplayPort 1.3 input (HBR3) from a 10 inch Mini DisplayPort connector. This is more compact for laptops. Desktops can add a DisplayPort to Mini DisplayPort adapter. A DisplayPort male connector would also work. It could use a female DisplayPort or Mini DisplayPort or USB-C connector with separate cable.
An optional power supply input for power delivery up to 100W (or the more usual 60W) in case a device requires more than the power supplied by USB-A or DisplayPort. If possible, make the USB and DisplayPort connections optional as well.
The TUSB1046-DCI with TPS65983B and TPD8S300 seem most relevant.